Gastric treatment and diagnosis device and method

ABSTRACT

A device, system and method for diagnosing and treating gastric disorders is provided. A functional device resides within the patient&#39;s stomach and is secured to the stomach wall by an attachment device. The functional device may be a sensor for sensing various parameters of the stomach or stomach environment, or may be a therapeutic delivery device. The functional device in one embodiment provides a device, system and method for gastric electrical stimulation where stimulating electrodes are secured to the wall of the stomach by the attachment device or otherwise. A preferred device includes: at least one stimulating electrode in electrical contact with the stomach wall; an electronics unit containing the electronic circuitry of the device; and an attachment mechanism for attaching the device to the stomach wall. The functional devices may be programmed to respond to sensed information or signals. An endoscopic delivery system delivers the functional device through the esophagus and into the stomach where it is attached the stomach wall. The endoscopic instruments attach or remove the attachment devices and functional devices from the stomach and may be used to assist in determining the optimal attachment location.

FIELD OF THE INVENTION

[0001] This invention relates to an implantable device, system andmethod for electrically stimulating the stomach wall to effect gastricmotility or otherwise treat gastrointestinal related disorders.

BACKGROUND OF THE INVENTION

[0002] Various organs of the gastrointestinal tract such as the stomach,small intestine and colon contain cells that are believed to govern theorgans' periodic contractile behavior. In healthy humans, in certainregions of the organs, these cells generate and propagate rhythmicelectrical signals. In general, several types of electrical potentialactivity have been observed in the gastrointestinal tract. Consistentslow wave or pacesetter potentials have been observed and higherfrequency spike activity has been observed. The pacesetter potentialsare continuously propagating, relatively low frequency, cyclicdepolarizations of the smooth muscle cell lining. The higher frequencyspike bursts correspond to some extent with smooth muscle contractileactivity and peristalsis. In general, when the spike burst activityoccurs, it appears to be at a fixed time delay with respect to the slowwave potentials. It is believed that when the pacesetter potentials arecombined with a chemical or neural excitation of the cells that smoothmuscle contractile activity occurs. Also it is believed that thepacesetter potentials control and coordinate the frequency and directionof the contractions.

[0003] Electrical stimulation of the gastrointestinal tract has beenproposed to treat motility related disorders and other gastrointestinaldiseases. The electrical stimulation has been proposed in a number offorms, such as, e.g., pacing, electrical contractile stimulation orother stimulation, e.g., to treat nausea or obesity. Electrical pacingof the gastrointestinal tract is generally defined as a periodicelectrical stimulation that captures and/or controls the frequency ofthe pacesetter potential or slow wave activity of the intestinal organ(including in a retrograde direction). Electrical contractilestimulation generally refers to stimulation that directly causes orresults in muscular contraction associated with the gastrointestinaltract

[0004] In some disease states, dysrhythmias of the gastric pacesetterpotentials may be present. The result of the abnormal pacesetterpotentials may be gastric retention of food. Electrical stimulation ofgastric tissue has been proposed to induce peristalsis. Electricalstimulation has also been proposed to treat obesity by altering gastricmotility, or by stimulating neural pathways. For example, one treatmentmethod causes the stomach to retain food for a greater duration.Electrical stimulation has also been proposed to slow the gastricemptying to treat a disorder known as dumping syndrome where the stomachempties at an abnormally high rate into the small intestine causingvarious gastrointestinal disorders. In particular, electrical pacing ofgastric pacesetter potentials has been proposed to induce regularrhythms for the pacesetter potentials with the intent of inducingregular or controlled gastric contractions.

[0005] Within the stomach, at least one pacemaker region has beenidentified near the interface of the fundus and the corpus along thegreater curvature. This region has been one target for gastric pacing.Peristalsis controlled by this region is believed to serve to mix andbreak down food and propel small particles through the pylorus into theduodenum. It is believed that gastric emptying of liquids is alsocontrolled by the fundus. This region is believed to create withcharacteristic contractions, a pressure gradient between the funduspylorus and duodenum that relates to the rate of gastric emptying.

[0006] An early attempt at a gastric stimulation device included anelectrode at the end of a nasogastric tube or catheter. The nasogastrictube was passed into the stomach transnasally. Electrical stimulationwas applied using an external stimulator unit through the electrode onthe end of the tube. The return electrode was placed on the abdomen.This device required a transnasal procedure whenever stimulation wasrequired.

[0007] Other devices used to pace the stomach have generally beenimplanted by accessing the outside of the stomach through an opening inthe abdomen, either through open surgery or laparoscopic surgery.Electrodes have been attached to the stomach wall with attached leadsextending through the abdomen.

[0008] These procedures involve implanting a pacemaker device in asubcutaneous or sub-muscular pocket. The devices are anchored into thesubcutaneous or sub-muscular pocket initially by a suture anchor andeventually by fibrous tissue ingrowth around the unit. The pacemakerdevice housing is typically constructed of a titanium or stainless steelmaterial with connectors molded into an epoxy header. The devices arethin in one dimension so that they are less visible when implanteddirectly under the skin or muscle layer. Therefore, in order toaccommodate the necessary battery capacity, the devices are widelyshaped, e.g. round or kidney shaped the other two dimensions. The leadsextend from the unit's epoxy header to a stimulation site remote fromthe pacemaker unit.

[0009] A gastrointestinal pacemaker having phased multi-pointstimulation has been proposed with electrodes placed in multiple pointsaround the GI tract including on the inner or outer surface of thestomach. As described, the device could be preprogrammed or include animplantable pacemaker detachably coupled to the multiple electrodes intheir various locations, and including an electronic controller that maybe programmed by using an external programmer to set stimulationparameters. The implantable pacemaker is located remote from thestimulation sites.

[0010] Some gastric stimulation procedures have proposed electricalstimulation in response to sensing electrical pulses within the stomachwithin a particular range. Additionally, a device has been proposed tosense electrical parameters to determine the fullness of an organ andthe absence of muscular contraction, and to deliver electrical muscularcontraction stimulation to the organ in response.

[0011] In general, the currently proposed gastric electrical stimulationprocedures are relatively invasive and require accessing the stomachthrough the abdomen, e.g., in an open or a laparoscopic procedure. Theunits have relatively wide dimensions in one plane. Accordingly, itwould be desirable to provide a less invasive procedure and device forelectrically stimulating the stomach.

[0012] A machine that places a nylon tag has been proposed for attachinga “payload” to the inner wall of a stomach. The machine places the tagthrough the stomach wall and back into the stomach in a manner thatcauses folding and may cause tissue damage when the smooth muscle of thestomach wall contracts. It would be therefore be desirable to provide anattachment device for attaching a device within the stomach wall thatminimizes device pull out forces, and that minimizes tissue damage whenthe smooth muscle of the stomach contracts, especially in electricallystimulating the smooth muscle of the stomach.

SUMMARY OF THE INVENTION

[0013] The present invention provides a device, system and method fordiagnosing and treating gastric disorders. The present invention furtherprovides a device, system and method for gastric electrical stimulation.Electrical stimulation is generally defined herein to mean anyapplication of an electrical signal or of an electromagnetic field totissue of the stomach for a therapeutic purpose. In one variation, thedevice is designed to facilitate or expedite mixing or breaking down offood matter or liquids in the stomach. In another variation, the deviceis designed to control, facilitate or expedite movement of food matteror liquids through the stomach and into the small intestine. In anothervariation, the device is designed to stimulate the stomach to delaypassage of food from the stomach and into the small intestine. Otherstimulation effects are also contemplated, including but not limited tousing stimulation to treat nausea, obesity or pain symptoms. Thestimulation may affect the smooth muscle contractions and/or nervesassociated with the stomach.

[0014] The stimulating (or diagnostic) device of the present inventionresides within the patient's stomach. A preferred device includes: atleast one stimulating electrode in electrical contact with the stomachwall; an electronics unit containing the electronic circuitry of thedevice; and an attachment mechanism for attaching the device to thestomach wall. One or more stimulating electrodes may be secured to thewall of the stomach by the attachment device. One or more stimulatingelectrodes may also be located on the electronics unit. In a preferredembodiment, at least one stimulating electrode is embedded in the wallof the stomach. Preferably the stimulation is provided through at leastone pair of bipolar electrodes. Alternatively a remote return electrodemay be provided in a monopolar device.

[0015] The attachment device may be either integrally formed with theelectronics unit or removably attachable to the electronics unit. Theattachment device and electronics unit may be deployed in two steps:first by identifying a site for attachment and attaching the anchor andsecond by attaching the electronics unit. The electronics unit may beremovable from the attachment device and or deployed electrodes so thatthe electronics unit may be replaced after time. The stimulatingelectrodes may be coupled to the attachment device and/or theelectronics unit. The attachment device may include, e.g., a mechanicalmeans such as a screw, suture, staple, clip or other anchor. Theattachment device may include a release mechanism for easy endoscopicremoval of the stimulating device from the stomach. In a preferredembodiment, the attachment device serves at least two functions: to holdthe device in place as well as providing the stimulation or sensing.Thus, the preferred stimulation device is both mechanically andelectrically coupled to the stomach. Another preferred embodiment mayinclude a stimulation device secured to the stomach with flexible leadsattached to the preferred stimulation site.

[0016] The stimulation device is constructed of size and shape such thatit can be deployed through the mouth and esophagus with the aid of anendoscope. As such, the electronics unit is preferably of a generallycylindrical shape. The device components are constructed of materialsthat allow it to withstand and function in the highly acidic environmentof the stomach for two or more years. (The pH in the stomach may be, attimes, as low as 1.0). Such materials are relatively inert to theenvironment. An example of such materials are: suitable inert polymers,for example, materials from the Polyolefin family like HDPE (highdensity polyethylene), LLDPE (linear low density polyethylene), andUHMWPE (ultra high molecular weight polyethylene); fluoropolymermaterials like PTFE™ (poly tetrafluoroethylene), FEP™ (fluorinatedethylene propylene) and others; polymethylpentene, and polysulphons;some elastomers such as thermoplastic polyurethanes and C-Flex typeblock copolymers that are stable in acidic environments. The electrodesare preferably made of corrosion resistant metals such as, e.g.Platinum, Gold, Tantalum, Titanium and corrosion resistant alloys or oneor more of these metals. The electronics unit or shell may alternativelybe constructed of one or more of these metals or alloys. Electrodes arepreferably coupled to the electronic circuitry through sealed electricalcontacts or through leads extending into the housing through moldedcorrosion resistant materials such as those described above.

[0017] A preferred system of the present invention includes anendoscopic delivery system for delivering the stimulator through theesophagus and into the stomach where it is attached the stomach wall.One embodiment of the system includes a flexible endoscope or endoscopicinstrument, for locating a preferred site in the stomach for deviceattachment. In one embodiment, the endoscope or endoscopic instrumentcomprises electrodes that may be placed on the inside of the stomachwall to measure electrical activity or impedance, or to deliver teststimulation pulsed to identify optimal stimulation parameters orlocations. The endoscope also provides one or more conduits throughwhich tools for attaching the device are inserted. In one variation ofthe system an endoscope is used to implant a stimulating device havingan anchor and a main body that is attached in situ to the attachmentdevice or anchor. Preferably the anchor attaches the electrode of thedevice to the stomach wall and the main body includes the deviceelectronics for providing the electrical stimulation through theelectrodes. Alternatively the electrodes may be attached to the stomachwall separately from the anchor. The system includes an endoscopicinstrument or instruments for first attaching the anchor and thencoupling the main body or electronics unit to the anchor. The device anddelivery system in a preferred embodiment includes a release mechanismin the stimulator unit so that it may be removably attached to an anchoror attachment device within the stomach so that the stimulator unit maybe exchanged if desired. A preferred embodiment of the endoscopic systemof the invention provides a device for engaging a release mechanism onthe attachment device or on the stimulator unit for disengaging thestimulator from the attachment device or for disengaging the attachmentdevice from the stomach wall.

[0018] In addition to the device being capable of stimulating thestomach wall, the electrodes of the device may also be used fordiagnostic purposes. For example, the electrodes may be used to senseand observe electrical activity in the stomach wall. Such sensing may beused over time to identify patterns, diagnose diseases and evaluateeffectiveness of various treatment protocols. For example irregular orlack of EMG activity may be sensed. Stimulation may be provided inresponse to sensed EMG activity or lack of activity.

[0019] In one variation, sensors can be included in the device orseparately for sensing various parameters of the stomach. The sensorsmay be mounted on the electronics unit, an attachment mechanism, or byother means, for example, in an independently attached device forexample attached with an anchor. The stimulation device may include amechanical sensor that senses, for example, stomach wall contractions.As the stomach contracts, the stomach wall typically becomes thicker. Ina preferred embodiment a device implanted in the stomach wall includes astrain gauge that is able to sense change in stomach wall thickness.Alternatively, electrical sensors may detect changes in impedance due tochanges in wall thickness from smooth muscle contractions. Otherexamples of such sensors may include, for example, pH sensors, impedancesensors, pressure sensors and temperature measuring devices such as athermocouple.

[0020] The stimulation device may be programmed to deliver stimulationin response to sensing electrical parameters or other sensed parameters.For example, a pH sensor may be used to determine when food has beeningested. When the pH changes in a manner, indicating food ingestion,the stimulation device may be instructed to deliver stimulation pulsesto stimulate gastric motility. The device may also be user controlled,where the recipient of the device is able to externally activate thedevice, for example by using an external unit which delivers a controlsignal via telemetry. A temperature sensor may be used, for example, todetermine when food has been ingested, by a change in temperature. Thedevice may begin stimulating the stomach upon detecting sudden change intemperature. Pressure sensors may be used to sense motility patterns,e.g. presence, strength or frequency of contractions. Mean pressureshifts may be observed to identify fundal contractility. The stimulationdevice may also use sensed parameters to program or reprogram the devicestimulation program. For example, measuring impedance changes through acircuit coupled to the electrodes (e.g., delivering a constant currentor voltage across the electrodes to determine impedance) or determiningthe contractile behavior of the stomach using a strain gauge, inresponse to stimulation pulses, the effectiveness of the stimulationpulses may be monitored and adjusted to provide optimal response. Thestimulation program may also include an automatic adjustment in responseto changes in pressure measurement.

[0021] Other diagnostic or treatment devices may be attached to theinside of the stomach wall, for example using a separate or integrallyformed anchoring device. Preferably such devices are introduced andattached to the stomach wall endoscopically. Such devices may include,for example, drug delivery devices, a gastric balloon, sensing ordiagnostic devices. In one embodiment when excessive acid concentrationis sensed using a pH sensor, a device is triggered to release an antaciddrug, e.g., using a drug delivery pump.

[0022] The present invention also provides an attachment device forattaching a functional device to the stomach wall. The functional devicemay be a sensor for sensing various parameters of the stomach or stomachenvironment, or may be a therapeutic delivery device. The devices may beattached to the attachment device in a separate housing or may beintegral with the attachment device. The functional devices may bepowered by a battery included with the device or the functional devicesmay be inductively powered. In a preferred embodiment, the attachmentdevice is attached such that the device does not substantially constrainthe stomach in the plane of smooth muscle contractions and to minimizestresses in the tissue, to reduce the potential for tissue damage ordevice dislodgement. Preferably the attachment device attaches in amanner that avoids folding of the stomach wall. In one preferredembodiment, the attachment device is attached by piercing at least aportion of the stomach wall at a single point of penetration into thestomach wall. Also, in one embodiment the attachment device pierces thestomach wall in a direction perpendicular to the natural orientation ofthe stomach wall. Further, in a preferred embodiment, the attachmentdevice extends through the stomach wall with a backing mechanism locatedexternal to the stomach wall. Preferably such backing mechanism isrelatively atraumatic to the stomach outer wall and surrounding tissueand has a relatively high surface area in relation to the width of theattachment device or puncture hole. Another preferred embodimentprovides an adjustable bumper holding the anchor to the inside of thestomach wall. Such bumper is also preferably designed to have arelatively high surface area and to be relatively atraumatic to thestomach wall. Another preferred embodiment provides an attachment devicewith a quick release mechanism that enables relatively easy endoscopicremoval of the attachment device from the stomach.

[0023] Preferred embodiments of various aspects of the invention aredescribed in the following detailed description.

DETAILED DESCRIPTION OF THE DRAWINGS

[0024]FIG. 1 is a partial cross sectional view of a system of a firstembodiment of the present invention in use in placing an electricstimulator in a patient's stomach.

[0025]FIG. 2 is a partial cross section view, illustrating placement ofan overtube in the first embodiment of the system of the presentinvention.

[0026]FIG. 3 is a partial cross sectional view of the placement of ananchor in the stomach in the first embodiment of the system of thepresent invention.

[0027] FIGS. 4-6 are detailed partial cross sectional views illustratingthe placement of the anchor in the first embodiment.

[0028]FIG. 7 is a side partial cross sectional view of the proximal endof an endoscope of the inventive system.

[0029]FIG. 8 is a side view of a distal end of the endoscope of theinventive system.

[0030]FIG. 9 is distal end view of the endoscope of FIGS. 7 and 8.

[0031]FIG. 10 illustrates a partial cut away side elevational view of ananchor of the first embodiment initially placed in the stomach wall

[0032]FIG. 11 illustrates a partial cut away side elevational view of afully deployed anchor of FIG. 10.

[0033]FIG. 12 illustrates a side elevational view of the main body ofthe stimulator of the first embodiment of the present invention.

[0034]FIG. 13 illustrates a side elevational view of the main body andanchor of the stimulator where a tether coupled to the anchor isthreaded through an opening in the main body to guide the main body tothe anchor.

[0035]FIG. 14 illustrates a partial cut away side elevational view ofthe stimulator of the first embodiment of the present invention attachedto the stomach wall.

[0036] FIGS. 15-17 illustrate respectively the main body of the firstembodiment of the stimulator as it is placed through the esophagus, intothe stomach and connected with the anchor.

[0037]FIG. 18 illustrates a side cross sectional view of the deployedanchor of FIG. 11.

[0038]FIG. 19 illustrates a side cross sectional view of the main bodyillustrated in FIG. 12.

[0039]FIG. 19A illustrates an enlarged view of the latch mechanism ofthe main body portion shown in FIG. 19 with the latch in a closedposition.

[0040]FIG. 20 illustrates an end cross sectional view of the main bodyillustrated in FIG. 12 with a quick connect in an open, unlockedposition.

[0041]FIG. 20A illustrates an enlarged view of the latch mechanism ofthe main body portion shown in FIG. 20 with the latch in an openposition.

[0042]FIG. 21 illustrates an end cross sectional view of the main bodyillustrated in FIG. 12 with a quick connect in a closed, lockedposition.

[0043]FIG. 22 illustrates a side cross sectional view of the main bodyand anchor of the first embodiment locked together.

[0044]FIG. 23 illustrates a side elevational view of the anchor and mainbody of a second embodiment of the stimulator of the present invention.

[0045]FIG. 24 illustrates a side elevational view of the embodiment ofFIG. 23 with the anchor and main body attached.

[0046]FIG. 25 illustrates a schematic diagram of the circuit of anelectronic stimulator of the present invention.

[0047]FIG. 26 illustrates a schematic diagram of the circuit of aprogrammer/recorder of the present invention.

[0048]FIG. 27A illustrates a third embodiment of the present inventionshowing an alternative anchor as it is inserted through the stomachwall.

[0049]FIG. 27B illustrates the anchor of FIG. 27A anchored to thestomach wall.

[0050]FIG. 28A illustrates a fourth embodiment of the present inventionshowing an alternative stimulation device.

[0051]FIG. 28B illustrates an enlarged view of an anchor of thestimulation device of FIG. 28A.

[0052]FIGS. 29A and 29B illustrate an alternative endoscopic instrumentfor placing an attachment device through a stomach wall

[0053]FIGS. 30A and 30B illustrate a fifth embodiment of presentinvention in which an anchor is placed using the instruments of FIGS.29A and 29B.

[0054]FIGS. 31A illustrates a sixth embodiment of the present inventionincluding an anchor and stimulator

[0055]FIG. 31B illustrates the anchor and stimulator of FIG. 31Battached within the stomach.

[0056]FIG. 32 illustrates a seventh embodiment of the present inventionincluding a screw in attachment device.

[0057]FIGS. 33A and 33B illustrate an eight embodiment of the presentinvention including an anchor with a clip on attachment device.

[0058]FIG. 34A and 34B illustrate a ninth embodiment of the presentinvention including an inductively powered stimulation device.

[0059]FIGS. 35A and 35B illustrate a tenth embodiment of the presentinvention including an endoscopic tool for mapping electrical activityin the stomach.

[0060]FIGS. 36A and 36B illustrate exemplary stimulation waveforms.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0061] Referring to FIGS. 10-14 and 18-22, a stimulator 10 of a firstembodiment is illustrated. The stimulator 10 comprises an anchor 123 anda main body portion 20. The anchor 123 comprises an elongate member 124having and expandable distal end 125 and a stimulating electrode 126 inthe form of a ring of a corrosion resistant metal conductor such asPlatinum, Gold, Tantalum, Titanium or suitable alloys thereof, extendingaround the elongate member 124 just proximal of the expandable end 125.The anchor 123 may be constructed of a radiopaque material.Alternatively, the anchor 123 may include radiopaque markers located onthe device so that the location and orientation of the device may beidentified, particularly after it has been placed. At least a portion ofthe anchor 123 is preferably coated with an antibiotic material, such asgentamicin sulphate or a silver/silver salts coating, particularly inlocations that it will extend through or come in contact with thestomach wall. A notch 127 extending around the elongate member 124 islocated proximally of the stimulating electrode 126, for connecting theanchor 123 to the main body portion 20, containing the stimulatorelectronic circuitry 25. An electrical contact member 128 comprising acorrosion resistant metal ring extends circumferentially around theelongate member 124 proximal of the notch 127. The electrode 126 and thecontact 128 are electrically coupled through a wire 129 or otherconductor extending through the elongate member 124. The proximal end ofthe anchor 123 has an opening 130. A tether 131 is secured to theopening 130. The tether 131 is used to guide the main body portion 20into place. The tether 131 is also used to pull on the anchor 123 whilethe main body portion is pushed into place both to provide a guide andto hold the anchor 123 in place.

[0062] A strain gauge 121 is located on the elongate member 124 of theanchor 123. The strain gauge 121 is coupled through conductors 121 a and121 b to electrical contacts 128 a, 128 b respectively. Electricalcontacts 128 a and 128 b are constructed and sealed when coupled to themain body 20, in a manner similar to contact 128.

[0063] The main body portion 20 comprises a sealed housing 21 includingelectronic circuitry 25. The electronic circuitry 25 provides sensing,stimulating electronic pulses through the electrodes to the stomachwall, and telemetry communication with an external unit such as areader, recorder or controller. The housing 21 includes an outer shellhaving a distal face 26 for interfacing with the stomach wall. The mainbody 20 also includes a radiopaque marker 31, preferably a radiopaquestimulator serial number (e.g., sprayed onto a location in the housing21) so that the device and its location may be identified. The outershell is constructed of an acid corrosion resistant material such as asuitable inert polymer, for example, materials from the Polyolefinfamily like HDPE (high density polyethylene), LLDPE (linear low densitypolyethylene), and UHMWPE (ultra high molecular weight polyethylene);fluoropolymer materials like PTFE™ (poly tetrafluoroethylene), FEP™(fluorinated ethylene propylene) and others; polymethylpentene, andpolysulphons; some elastomers such as thermoplastic polyurethanes andC-Flex type block copolymers that are stable in acidic environments.Additionally the outer shell may be constructed of an acid corrosionresistant metal such as Platinum, Gold, Tantalum, Titanium, or suitablealloys thereof. The distal face 26 is preferably coated with anantibiotic material, such as gentamicin or silver/silver salts coating.The main body 20 further comprises an electrode 32 located on the distalface. The electrode 32 is constructed of an acid corrosion resistantmaterial such as Platinum, Gold, Tantalum, Titanium, or any suitablealloys thereof.

[0064] The main body portion 20 further comprises a channel 23 throughwhich the tether 131 is threaded for alignment with the anchor 123 (FIG.13) and for receiving the elongate member 124 of the anchor 123 (FIGS.14 and 22). A second channel 23 a extends parallel to the channel 23from an opening in the proximal side of the main body 20 and endingwithin the main body 20. The second channel 23 a is for receiving aconnect/release tool 38 described in more detail below.

[0065] The channel 23 includes an opening 24 in the distal face 26 ofthe body portion 20 as well as an opening 22 a in the proximal side 22of the main body 20. The walls of the channel 23 include a plurality ofacid resistant elastomeric seals 27 formed of a material such as, forexample, polyurethanes, rubbers or C-Flex type block copolymers. Inbetween the seals 27 is a flexible electrical contact 28 for contactingthe electrical contact 128 of the anchor 123 and a latch 29 for engagingthe notch 127 of the anchor 123. Thus, the electrical contact 28 will belocated in a sealed area of the channel 23, between seals 27, protectingit from the highly acidic environment of the stomach. The seals 27 alsoact as electrical insulators that prevent unintended current pathwaysbetween the electrical contact 28 and the electrode 32. The electricalcontact 28 is coupled to the electronic circuitry 25 of the main bodyportion 20 through a conductor 30 extending from the circuitry 25through the housing 21 to the contact 28. The second stimulatingelectrode 32 located on the distal face 26 of the main body 20 iscoupled to the electronic circuitry 25 by way of a conductor 33. As analternative to being coupled to the electronic circuitry through asealed contact, the electrode 126 may be constructed in a manner similarto electrode 32 using a corrosion resistant material that is directlycoupled to the electronic circuitry (for example, where the anchor isintegrally formed with the stimulator 10 or where the electrode 26 islocated on the housing).

[0066] As illustrated in FIG. 22, when the main body portion 20 and theanchor 123 are connected, the elongate member 124 of the anchor 123extends into the channel 23 so that the notch 127 and the electricalcontact 128 are located between seals 27. The electrical contacts 128,128 a, and 128 b are in contact with flexible electrical contacts 28, 28a, and 28 b respectively, and the latch 29 is located within the notch127 so that the elongate member 124 of the anchor 123 is fixed withinthe main body portion 20.

[0067] FIGS. 19-21 show the latch mechanism 29 in the main body 20 thatis used to connect the main body 20 to the anchor 123. The latch 29 islocated within a closed channel 34 in the main body 20 that is orientedperpendicular to the channels 23 and 23 a. A spring member 36 is locatedat the end 35 of the closed channel 34 between the end 35 and the latch29. The spring 36 biases the latch 29 in a closed position asillustrated in FIG. 20 and described below. The latch 29 comprises aconnecting end 29 a that extends into the channel 23 when the latch 29is in its closed position. The latch 29 further comprises an opening 29b formed in part by a cam surface 29 c ending in tip 29 d. When thelatch 29 is in an open position (FIG. 19), the spring 36 is compressedand the cam surface 29 a and the tip 29 d are recessed into the closedchannel 34. When the spring 36 is released, the latch 29 moves into theclosed position where the cam surface 29 a extends into the channel 23and the cam surface 29 c and tip 29 d extend into the channel 23 a.

[0068] In use, the latch 29 tends toward the closed position. In orderto connect the anchor 123 with the main body 20, a connecting tool 38 isinserted into the channel 23 a and the tool 38 engages the cam surface29 c to move the latch 29 into the open position. Channel 23 a includesan elastomeric, self-sealing plug 23 b with a slit for receiving theconnecting tool 38. The plug 23 b seals the opening in the channel 23 afrom external fluids, etc. The tool 38 includes a notch 39 in its distalend. The tool 38 may be locked into position in the channel 23 a byrotating the tool so that the tip 29 d of the cam surface 29 c engagesthe notch 39. This prevents removal of the tool 38 from the channel 23a. Thus the tool 38 may be temporarily locked in the channel 23 a withthe latch 29 in an open position for insertion of the anchor 123 intothe channel 23. The tool 38 may be released when the anchor 123 is inplace, by rotating the tool so that the tip 29 d of the latch 29 nolonger engages the notch 39 in the tool 38. When connected, the elongatemember 124 of the anchor 123 is located in the channel 23 and the latchconnector 29 a extends into the notch 137 in the elongate member 124,thereby connecting the anchor 123 and the main body portion 20.Alternatively, the main body portion 20 may be connected to the anchor123 without the use of such a tool. In this case, the anchor 123 causesthe latch to retract as the anchor 123 is inserted until the connectingend 29 a of the spring-loaded latch 29 locks into place in the notch137.

[0069] The tool 38 may be used in a similar manner as described above,to remove the main body 20 from the anchor 123, for example to replacethe main body 20 or remove the stimulator 10. The tool 38 is preferablya device that may be inserted through a lumen in an endoscope. In suchcase, the tool 38 may first be placed through the endoscope and attachedto the stimulator distal of the endoscope's distal end. This wouldparticularly be the case where the stimulator is larger than thechannels in the endoscope. Other endoscopic tools may be used to deployor remove the stimulator 10 or main body 20. For example, a graspingtool may be used manipulate the device where the grasping tool has anactuator handle extending out of the proximal end of the endoscope. Alsoa magnetic tool may be used to engage and manipulate the stimulatorduring insertion or removal. A magnetic docking system may be used aswell, to locate or orient the main body 20 in an aligned position withrespect to the anchor 123. The main body, anchor insertion tool orendoscope may have magnets that provide for aligned connection betweenthe main body 20 and anchor 123.

[0070] FIGS. 1-9 and 15-17 illustrate an endoscope of the system of thepresent invention and the placement of the electrical stimulator 10using the endoscope and associated instruments. FIG. 1 illustrates aflexible endoscope 110 such as, for example, of a type that used bygastroenterologists in treating the upper gastrointestinal tract. Theendoscope 110 is used to locate an attachment site in the stomach 100and attach the stimulator device 10 to the stomach wall of a patient.The flexible endoscope is of the type that is typically used bygastroenterologists in accessing the esophagus or stomach. The endoscopeallows the physician to visualize while performing procedures on theupper gastrointestinal tract. The flexible endoscope may be, forexample, a flexible fiber optic endoscope utilizing optic fibers forimaging or a video endoscope that uses a CCD (charge coupled device) toprovide video images. Such endoscopes typically include a fiber opticlight guide and a complex objective lens at the distal end to focus theimage.

[0071] As illustrated in FIGS. 7-9, the endoscope comprises an elongatetube having a proximal handle portion 106 and a distal portion 115. Theendoscope includes an aspiration channel 112 and irrigation/air channel113. A fiber optic light source 93 for illuminating the stomach siteextends through a fiber optic channel. A video lens 94 is located at thedistal end of the endoscope, for receiving and focusing the image thatis transmitted back through a channel in the endoscope 110.Corresponding light source input 95, video output 96, irrigation port97, aspiration port 98 and auxiliary port 99, are located on theproximal handle portion 106. Knobs 107 and 108 are coupled at theproximal handle 106 for left/right and up/down steering mechanisms,respectively, that are used to steer the distal portion of the endoscopein a manner that is generally known to one of ordinary skill in the art.The endoscope 110 further includes an auxiliary channel 114 extendingthrough the endoscope 10 and providing an opening through which surgicalinstruments may extend to reach the site 105. An additional auxiliaryport may be provided for additional instruments or alternatively, theaspiration channel 112 may be used for additional tools if not otherwiserequired in a procedure. The distal portion 115 of the endoscope 110includes an open distal tube 116, the end of which is placed against thestomach wall at the site 105. The distal tube 116 provides a space forstomach tissue to enter and be held in place when a vacuum pressure isapplied.

[0072] During the procedure the patient is given a numbing agent thathelps to prevent gagging. As shown in FIG. 2 a protective overtube 111with the endoscope 110 is passed through the mouth 101, pharynx 102,into the esophagus 103 and opening into the stomach 100. The overtube111 is used to protect the esophagus, which may become irritated withrepeated insertion and removal of instruments. The overtube 111 alsohelps prevent instruments and devices from inadvertently dropping intothe trachea. In addition, the overtube 111 serves to protect the toolsfrom the bacteria in the mouth and esophagus so that such bacteria arenot passed on to the stomach wall. As illustrated in FIG. 9, theovertube 111 a may also include additional channels 111 a and 111 b forinserting additional instruments.

[0073] Preferably the instruments inserted into the patient's stomachare coated with an antibacterial material, in particular, theinstruments that are used to pierce or otherwise come in contact withthe stomach wall. As illustrated in FIG. 3, the endoscope 10 is extendeddistally out of the overtube 111 and is used to locate a site 105 on thestomach 100 for attaching the stimulator 10. Additionally oralternatively, an endoscope or a tool inserted through the esophagus maybe used to detect intrinsic gastric electrical activity to help pinpointthe optimal site for a stimulator and/or electrode attachment to thestomach wall (See for example, FIG. 35A and 35B and the correspondingdescription herein). In such a case sensing electrodes are coupled tothe distal end of the endoscope or tool, with conductors extend out ofthe endoscope or patient's esophagus to a unit having a controller forreceiving sensed electrical activity and identifying a surgical site forstimulator attachment.

[0074] As shown in FIGS. 4-6 an introducer 117 is inserted through theauxiliary channel 114. The introducer 117 comprises an outer cannula118, a dilator 119 extending through the cannula 118, and a needle 120extending through the dilator 119. Each of the cannula, 118, dilator 119and needle 120 are separately actuable at the proximal end in a mannerthat would be apparent to one of ordinary skill in the art, for example,in a manner similar to such devices utilized in catheter introducersets. After the open distal tube 116 is located at a site 105 in thestomach 100, a vacuum pressure is applied through the aspiration channel112 to engage, stabilize and hold the tissue at the site 105. Asillustrated in FIG. 4, the needle 120 is advanced distally through thetissue of the stomach wall. As illustrated in FIG. 5, the dilator 119 isthen advanced over the needle 120 through the stomach wall. The needle120 is then retracted proximally out of the dilator 119 and is removedfrom the endoscope 110. The cannula 118 is advanced over the dilator 119and the dilator 119 is removed proximally from the endoscope 110.

[0075] As illustrated in FIG. 6, with the cannula 118 through thestomach wall, the anchor 123 may be placed into the cannula 118 from theproximal end of the endoscope. Using a push tube 122 having a diameterthat is small enough to fit within the cannula 118, placed proximally ofthe anchor 123, the anchor 123 is distally advanced through the cannula118 located within the stomach wall (FIG. 10).

[0076] The push tube 122 pushes the anchor 123 through the cannula 118until the expandable distal end 125 extends out of the stomach wall inthe peritoneal cavity. (FIG. 11) Before insertion, a tether 131 issecured to the opening 130 and extends through the push tube 122 out ofthe proximal end of the endoscope 110. The expandable distal end 125 isformed of an elastic or spring material that tends to spring open intoits expanded shape when the distal end 125 is no longer constrained bythe cannula 118. (FIG. 11). Once the anchor 123 is in place, the cannula118 is withdrawn from the endoscope 110 and the endoscope 110 may alsobe removed from the over tube 111 leaving the tether 131 in placeextending from the anchor 123 out of through the over tube 111 and outof the patient's mouth 101. The tether 131 is to be used to guide themain body 20 of the stomach to the anchor 123. The tether 131 maycomprise a thread or suture-like device or may be a thin flexible guidewire like device. The tether 131 may be tied or otherwise anchored tohole 130 in anchor 123 or it may be looped through hole 130 in anchor123 such that two strands lie parallel to each other in the overtube 111and pass out of the patient's mouth.

[0077] FIGS. 15-17 illustrate a preferred procedure for connecting themain body portion 20 of the stimulator 10 to the anchor 123 in place inthe stomach wall. The main body 20 is threaded on to the tether 131 thatis attached to the anchor 123 through the channel 23 in the main body20. The tether 131 which extends through the over tube 111, guides thechannel 23 to the elongate member 124 of the anchor 123 for attachment.The threaded main body portion 20 is preferably placed within the overtube 111 with the endoscope 110 located proximal of the main bodyportion 20 within the overtube 111. The tether 131 is also preferablythreaded through the overtube 111, placed in parallel with the endoscope110 through the overtube 111 or one of its channels 111 a, 111 b. Thetether may be placed in a lumen extending through the endoscope 110.Tool 38 extends through the auxiliary channel 114 and is coupleddistally of the distal end 115 of the endoscope, to the main body 20through the channel 23 a. The endoscope 110 distal portion 115 alsoengages the main body portion 20 and provides a force to move the mainbody portion 20 through the over tube 111. (FIG. 15). The endoscope 110further provides visualization of the coupling process. The tool 38 andtether 131 together further locate the main body portion 20 with theanchor 123 as it extends through the stomach 100 to the site 105. (FIG.16). Finally, the tool 38 provides additional force to attach the mainbody portion to the anchor 123 (FIG. 17). The tool 38 is then removedfrom the channel 23 a in the main body 20 and out of the endoscope'sproximal end. Alternatively the main body 20 may be placed in position,coupled to the anchor 123 by using the tether 131 and the distal portion115 of the endoscope to guide the main body 20 into place. (See e.g.,FIGS. 15-17). In an alternative embodiment, a magnetic docking system isused wherein the distal end 115 of the endoscope 110, main body 20,and/or anchor 123 includes a magnet and/or corresponding metal used toalign and position the anchor 123 and main body 20 with respect to eachother.

[0078] After the main body portion 20 has successfully been coupled tothe anchor 123, an endoscopic scissor or other cutting device may beprovided through the auxiliary channel 114 in the endoscope 110 to cutthe tether 131. As illustrated in FIG. 14, when the stimulator isattached to the stomach wall, the stimulating electrode 32 is locatedwithin the tissue of the stomach wall, providing electrical contact.While the second stimulating electrode 32 on the distal face 26interfacing with the stomach 100, is in electrical contact with theinner surface 100 b of the stomach wall.

[0079]FIGS. 23 and 24 illustrate a second embodiment of the stimulatorof the present invention. Stimulator 210 comprises a main body portion220 and an anchor 223. The anchor 223 comprises an elongate proximalmember 225. The elongate proximal member 225 includes a tether opening235 in the proximal end, electrical contacts 228, 238, and a notch 227for connecting the main body portion 220 to the anchor 223. The distalportion 240 of the anchor 223 comprises two prongs 241, 242. Prongs 241,242 have expandable distal ends 243, 244 respectively that areconstructed in a similar manner as the expandable distal end 125described above with respect to the first preferred embodiment. Astimulating electrode 245 is located on prong 241 and an electricallyopposite second stimulating electrode 246 is located on prong 242.Stimulating electrode 245 and second stimulating electrode 246 arecoupled to electrical contacts 228 and 238 respectively by conductors229 and 239 extending through prongs 241, 242 respectively into theelongate proximal member 225. Prongs 241 and 242 are connected by aspacer 237.

[0080] Main body portion 220 includes a channel 215 with an opening 216on the distal face 226. The channel 215 and the opening 216 on thedistal face have shapes that allow them to respectively receive theelongate proximal member 225 and the spacer 237, thereby sealing theopening 216. The electrical contacts 228, 238 to the anchor 223 arecoupled to electrical contacts within the channel 215 of the main bodyportion 220 in a manner similar to the coupling of contacts 128, 128 aand 128 b of anchor 123 and contacts 28, 28 a, and 28 b of main bodyportion 20 described with reference to the first embodiment herein. Alsothe notch 227 engages a latch similar to the latch 29 described above.The notch 227 and latch and the electrical contacts 228, 238 areisolated from the acidic environment of the stomach using seals such asthe seals 27 described above with respect to the first embodiment.Alternatively, the electrodes 245, 246 may be constructed in a mannersimilar to electrode 32 using a corrosion resistant material that isdirectly coupled to the electronic circuitry (for example, where theanchor is integrally formed with the stimulator or where one or more ofthe electrodes 245, 246 are located on the main body portion).

[0081] The anchor prongs 241, 242 may be deployed in a similar manner asanchor 123 is deployed, using a dual needle introducer or, alternativelyby deploying each prong 241, 242 independently and later connecting theprongs 241, 242 with the spacer 237.

[0082] In use, once the stimulator (e.g., 10, 210, 310 or 380) isdeployed, electrical stimulation is provided through electroniccircuitry 25. The electronic circuitry 25 is capable of producingvarious types of programmable waveforms. FIGS. 36A and 36B illustrateexamples of stimulation waveforms that may be used in stimulating thesmooth muscle lining of the intestinal tract. FIG. 36A illustrates awaveform design for stimulating the intestinal tract at a pacing rate.In a preferred embodiment, the waveform 1 has a pulse amplitude ofbetween 0.5 and 20 milliamps, a pulse width of between 0.5 and 10milliseconds, and a frequency of about between 1 and 5 pulses perminute. FIG. 36B illustrates an alternative waveform design forstimulating the intestinal tract. The waveform 2 utilizes bursts ofpulses rather than a single pulse with a burst repetition rate to beselected, preferably of about 3 cycles per minute. The duration of aburst in this example is about 100 ms and an amplitude of about 10 mA.In this example, the frequency of the burst pulses during a burst isbetween about 50 to 100 Hz, and as is well known to those skilled in theart, there are many different types of electrical stimulation programsand strategies which can be utilized for providing electricalstimulation parameters through the circuitry 25, the principal focusbeing providing electrically stimulating parameters for the stomach.

[0083] A preferred embodiment of the electronic circuitry 25 isillustrated in FIG. 25. The electronic circuitry 25 of the stimulator islocated in the main housing. The circuitry 25 comprises, amicroprocessor or controller 40 for controlling the operations of theelectronic circuitry 25, an internal clock 41, and battery device 44such as a pair of lithium iodine batteries for powering the variouscomponents of the circuit 25. As such, the controller 40 and batterydevice 44 are coupled to each of the major components of the circuit aswould be apparent to one of ordinary skill in the art. The controller 40is coupled to stimulation driver 42, which is coupled to stimulatingelectrodes (e.g., 126, 32 or 245, 246) that are used to provideelectrical stimulation in accordance with programmed parameters

[0084] The controller 40 is coupled to ROM 43, which contains theprogram instructions for the controller 40 and any other permanentlystored information that allows the microprocessor/controller 40 tooperate. The controller 40 addresses memory in ROM 43 through addressbus 43 a and the ROM 43 provides the stored program instruction to thecontroller 40 via data bus 43 b. The controller 40 controls thetelemetry coil 45, which communicates with an external control orprogramming device 60 (FIG. 26), preferably via a modulated RF signal.Processor 40 is coupled to an oscillator 51 that provides an RF signalto be emitted from the telemetry coil 45. The RF signal is preferably atabout 500 kHz or higher so that the signal is efficiently transmittedthrough tissue. The controller 40 controls the oscillator 51 andprovides data to be modulated with the RF signal. For example, varioussensed data such as pressure, pH, temperature, strain, impedance,electrical activity (EMG) etc., may be delivered through the telemetrycoil 45.

[0085] The circuit 25 may also be coupled through A/D converters 46 a,46 b, 46 c, 46 d to one or more sensors 47 a (e.g., strain gauge), 47 b(e.g., pressure), or electrodes 32, 126. Suitable types of these sensorsare generally known in the art and may be located within, on, orexternal to the housing 21 of the main body portion 20. Controller 40 iscoupled to RAM 50 via an address bus 50 a for addressing a location inRAM 50 and a bi-directional data bus 50 b for delivering information toand from RAM memory 50. The RAM memory 50 includes event memory 48 thattemporarily stores data recorded by sensors 47 a, 47 b, 32 and 126 and aprogrammable memory 49 which may be programmed, for example, by anexternal programmer 60, to provide treatment protocols, e.g. to specifyoperating modes such as waveform, frequency, etc. The strain gauge 47 ais coupled through A/D converter 46 a, which converts the representativeelectrical signal output by the strain gauge into a digital signal,which is delivered to the microprocessor/controller 40 and stored in theevent memory 48 in the RAM 50. The sensor 47 b is coupled through A/Dconverter 46 b, which converts the representative electrical signaloutput by the sensor 47 b into a digital signal, which is delivered tothe microprocessor/controller 40 and stored in the event memory 48 inthe RAM 50. The electrodes 32, 126 are coupled through A/D converters 46c and 46 d to the microprocessor 40. A/D converter 46 c converts theelectrical EMG signal sensed by the electrodes 32, 126 into a digitalsignal representative of the EMG electrical activity, which is deliveredto the microprocessor/controller 40 and stored in the event memory 48 inthe RAM 50. Also, the A/D converter 46 d converts the electrical signalsensed by the electrodes 32, 126 and provided through the impedancecircuit 53 described below, into a digital signal representative oftissue impedance, which is delivered to the microprocessor and stored inthe event memory 48 in the RAM 50. The data stored in the event memory48 may be sent intermittently as data bursts via the telemetry RF coil45, as opposed to continuously in order to save battery power.

[0086] The electrode 32, 126 outputs are used to provide electricalstimulation delivered through the stimulation driver 42 to electrodes.The stimulation modes and parameters can either be set using theexternal programmer 60, or they may be set in response to sensoryfeedback. The same electrode outputs are used to sense impedance throughimpedance circuit 53 and to sense electrical activity which is deliveredthrough driver 56 c. The electrodes 32, 126 are coupled through couplingcapacitors 55 a and 55 b respectively, to output of electricalstimulation driver 42 and input of drivers 56 c, 56 d.

[0087] The impedance circuit 53 comprises a constant current sourceoscillator 54 that oscillates at a frequency of 50-100 kHz, and a driver56 d coupled through A/D converter 46 d to the controller 40. Theoscillator 54 provides a constant current source through electrodes 32,126 resulting in a voltage across the electrodes 32, 126 that isrepresentative of impedance, in view of the constant current. Thevoltage is provided through driver 56 d and is converted by A/Dconverter 46 d to a digital signal representative of impedance. Driver56 d has a bandwidth that includes the 50 kHz frequency signal whilefiltering out the electrical stimulation signal that is delivered to theelectrodes 32, 126 through electrical stimulation driver 42, and the EMGsignal that is sensed by the electrodes 32, 126. Both of the outputs arefiltered out by driver 56 d. Driver 56 c which delivers the EMG signalto A/D converter 46 c, also has a bandwidth that filters out the 50-100kHz signal. Further, when a stimulation signal is being delivered, thecontroller 40 does not receive signals from A/D converters 46 c and 46d. Thus the EMG and impedance sensing functions and the stimulationdeliver functions are separated through the electronic circuitry 25,though using the same electrodes.

[0088]FIG. 26 illustrates the electronic circuitry 63 for externalprogrammer 60. The electronic circuitry 63 comprises: a microprocessoror controller 70 for controlling the operations of the electroniccircuitry, an internal clock 71, and a power source 74 such as batterydevice for powering the various components of the circuit 63. As such,the controller 70 and battery device 74 are coupled to each of the majorcomponents of the circuit as would be apparent to one of ordinary skillin the art. The controller 70 is coupled to a speaker 67 for thatprovides audible alerts and a display 66 such as a CRT to display datasuch as recorded data, sensed parameters treatment parameters and statusof device (e.g. position or battery charge status). The controller 70 iscoupled through a buffer 64 to external input device 65 that is used toprovide program parameter input, e.g. from a user, for a user to requestdata displayed in a desired format through display 66 or speaker 67, orto turn device on and off. The external programmer 60 is also providedwith an external data port 68 to interface with a computer and provide ameans for bi-directional communication of data or commands. The computermay provide programming or data to the controller/microprocessor 70. Auser may also interface with the computer to provide treatment protocolsor changes in protocols, etc. Also, a user may control the turning onand off of the stimulation program.

[0089] The controller 70 is coupled to ROM 73, which contains theprogram instructions for the controller 70 and any other permanentlystored information that allows the microprocessor/controller to operate.The controller 70 addresses memory in ROM 73 through address bus 73 aand the ROM 73 provides the stored program instruction to the controller70 via data bus 73 b. The controller 70 controls the telemetry coil 75,which communicates with stimulator electronics 25 (FIG. 25) through itstelemetry coil 45. Processor 70 is coupled to an oscillator 72 thatprovides an RF signal, preferably having a characteristic frequency of500 kHz or higher, to be emitted from the telemetry coil 75. Thecontroller 70 controls the oscillator 72 and provides data to bemodulated with the RF signal, for example, programming information,stimulation parameters, etc. The telemetry coil 75 also receivesinformation transmitted via RF signal from telemetry coil 45 on thestimulator 10 such as-various sensed data, e.g., pressure, pH,impedance, electrical activity (EMG) etc. The received RF signal ispassed through A/D converter 76 and is transmitted to the controller 70.The data is delivered to the event memory 78 in RAM 77 by way of databus 77 b for temporary storage. The data may be retrieved from RAM 77 byaddressing the storage location via the address bus 77 a.

[0090] Event memory 78 temporarily stores data recorded by sensors 47a-47 c and delivered via telemetry to the external programmer 60, untilthe data is downloaded onto a computer using the external data port 68.The RAM 77 also includes a programmable memory 79 which may beprogrammed, for example, to specify operating modes such as waveform,frequency, etc which programming is then telemetrically communicated tothe stimulation device 10, 210. The modes and parameters can either beset using an external programmer 60 or set in response to sensoryfeedback.

[0091]FIGS. 27A and 27B illustrate a third embodiment of the presentinvention showing an anchor device for use with a stimulator or otherfunctional device of the present invention. The anchor 263 comprises anelongate body 264, an expandable distal portion 265 having a sharp tip270, a bipolar electrode pair 266, 267, and a bumper 275 located on aproximal portion of the elongate body 264. The expandable distal portion265 comprises a flexible disk 271 for engaging the outer stomach wall.The disk 271 has an inner surface 271 a that interfaces with the outersurface 100 a of stomach wall 100 and may, for example be coated with anantibiotic material, such as gentamicin sulphate or a silver/silversalts coating such as a powder. The bipolar stimulating electrode paircomprises electrode 266 located on the elongate body 264 and a pluralityof electrodes 267 electrically opposite from electrode 266, located atthe end of the expandable distal portion 265. The electrodes may beseparately coupled to electrical contacts and may be individuallyselected to provide optimal stimulation pulses, for example, based oncontractile response when stimulation pulses are delivered to aparticular electrode or electrodes. Electrode 266 is ring extendingcircumferentially around the elongate body 264. Electrodes 267 arecircumferentially spaced from each other around the radial extremity 271b of the disk 271. As an alternative to a plurality of electrodes 267the electrode located on the disk may be a single ring electrode.Electrodes 266, 267 are electrically coupled to a main body portioncontaining electronic circuitry (not shown) that is attached in a mannersimilar to main body portion 20 described above. Conductors 268, 269electrically couple electrodes 266, 267 respectively to the electroniccircuitry of the main body portion.

[0092] The anchor 263 may be deployed without requiring an introducersuch as described above with reference to FIGS. 4-6. As illustrate inFIG. 27A, the sharp tip 270 is used to pierce the stomach wall 100. Theflexible disk 271 folds within recessed portion 265 a extending aroundthe distal portion of the anchor 263 so that the disk 271 is flush withthe outer surface of the elongate body 264 and forms a taper to thesharp tip 270. The tip 270 is preferably conically tapered so as toatraumatically dilate the stomach wall as it is inserted and help insurea good seal formed by the elastic rebound of the stomach wall tissuearound the elongate body 264.

[0093] Referring to FIG. 27B as the distal portion 265 of the anchor 263extends through the stomach wall, the expandable disk 271 opens. Theanchor 263 is retracted slightly so that the radial extremity of thedisk 271 engages the outer surface 100 a of the stomach wall 100,preventing proximal movement of the anchor 263. The electrodes 267 arein electrical contact with the outer surface 100 a of the stomach wall.The electrode 266 on the elongate body 264 is embedded within thestomach wall 100 and is in electrical contact with the tissue therein.The bumper 275 may be advanced distally so that is engages the innersurface 100 b and secures the anchor 263 in position, preventing distalmovement. Preferably the bumper 275 and the disk 271 lock the anchor inplace and may also further serve to help seal the opening formed in thestomach from the acidic internal stomach environment and the environmentexternal the stomach wall 100. The bumper 275 may be secured in positionby a ratchet mechanism or other means such as a frictional fit. The tip270 is constructed of a bioabsorbable material such a glucose basedabsorbable material or polyglycolic acid or polylactic acid, so that thesharp tip 270 readily dissolves and is absorbed by the body, preventingthe tip from injuring tissue external to the stomach.

[0094]FIGS. 28A and 28B illustrate a fourth embodiment of the presentinvention showing a stimulator. Stimulator 310 comprises an anchor 323,an electronics unit 320 and electrodes 326, 327 coupled by leads 328,329 respectively to the electronics unit 320. The stimulator 310 isattached to the inner surface 100 b of the stomach wall 100 by anchor323 which may be constructed or attached in a manner similar to anchors123, 223,or 263 described above, either with or without electrodes. Theelectrodes 326, 327 are anchored into the stomach wall 100 with anchors324, 325 respectively. Referring to FIG. 28B, an anchor 325 is showndeployed in the stomach wall 100. Lead 329 extends from the main bodyportion 320 through the stomach to the site 105 where stimulation isdesired. The anchor 325 is preferably constructed in a manner similar toanchor 263 with a bioabsorbable or resorbable tip and so that theelectrode 327 is embedded in the stomach wall 100. The ends of the leadsare molded into the housing using corrosion resistant materials suitablefor long term use in the stomach. Adjustable sealing ring or bumper 321operates to prevent anchor 325 from moving out of the stomach and mayhelp to seal the opening in the stomach wall formed by the anchor fromthe acidic stomach environment and. Anchor 324 is deployed in a similarmanner with electrode 326 embedded in the stomach wall 100 at the site105 for stimulation. Preferably the stimulating electrodes 326, 327 arelocated at a distance from each other between 5 and 10 mm so that theelectrical stimulation is delivered efficiently to the area of interest.The electronic circuitry of the main body 20 delivers electricalstimulation in a manner similar to the stimulation device 10 describedabove.

[0095] Referring now to FIGS. 29A and 29B, an alternative instrument isillustrated for placing an anchor from the inner surface 100 b of thestomach wall 100 through to the outer surface 100 a of the stomach wall.The instrument 330 comprises a hollow piercing needle 331 having a lumen332 therethrough and a stomach piercing tapered distal end 333. A guidewire 334 extends through the lumen 332 in the needle 331. The needle 331is relatively stiff to allow it to pierce the stomach wall while theguide wire 334 is more flexible. As illustrated in FIG. 29A, the distalend 115 of the endoscope is located at a desired site on the inside 100b of the stomach wall 100. A vacuum pressure is applied to the wall tostabilize it and the needle 331 pierces the stomach wall through asingle point, preferably in a direction that is substantiallyperpendicular to the natural orientation of the stomach wall to preventfolding of the stomach wall and tearing forces during smooth musclecontraction, at the point of attachment. As illustrated in FIG. 29B, theneedle 331 is removed, leaving the guide wire 334 in place. Preferably,the instrument 330 is inserted through the auxiliary channel 114 in theendoscope or through a channel 111 a or 111 b in the over tube 111 andthen is located to the desired site using the endoscope 110 forvisualization.

[0096] Referring to FIGS. 30A and 30B, an anchor 340 is illustratedplaced into the stomach wall 100 over the guide wire 334. The anchor 340includes an elongate member 341 that is to be placed through the stomachwall 100 in a direction substantially perpendicular to the stomach wall.The anchor 340 has a distal portion 343 that is to at least partiallyextend through the stomach wall, and a proximal portion 342 having athreaded proximal end 342 a for engaging with a threaded end of aninstrument used to advance the anchor 340 into place. The anchor 340includes a guide wire lumen 345 extending through the anchor 340 fromthe proximal portion 342 to the distal portion 343 with an opening inthe proximal portion 342 and distal portion 343 for receiving the guidewire 334 of the insertion instrument 330. As shown in FIG. 30A, theanchor 340 is inserted over the guide wire 334 which guides the anchor340 into position through the stomach wall 100. The guide wire lumen 345at the distal portion 343 of the anchor 340 is sealed with aself-sealing plug 344 formed of an elastomer and having a slit along theplug 344 so that the guide wire 334 can open the plug 344 while theguide wire 334 extends through the lumen 345.

[0097] An expandable member 348 is located on the distal portion 343 ofthe anchor 340. The expandable member 348 comprises a balloon formed ofeither a compliant or non-compliant material such as, e.g.,polyurethane, polyethylene or polyester bonded to the outer surface ofthe distal portion 343 of the anchor 340 and providing an inflationchamber 350. Accordingly, the balloon may be inflated to a predeterminedpressure (typically using a non-compliant material) or a predeterminedvolume (typically using a compliant material). An inflation lumen 351extends from an opening in the proximal portion 342 to an opening 349 inthe distal portion 343. The opening 349 in the inflation lumen 351 is influid communication with the inner chamber of the expandable member 348so that an inflation medium may be supplied through the inflation lumento inflate the expandable member 348. As illustrated in FIG. 30B, theanchor 340 is placed in the stomach wall and the expandable member 348is inflated by supplying the inflation chamber 350 with an inflationmedium. In a preferred embodiment, a curable elastomeric polymer is usedas an inflation medium, e.g., a two-part curable elastomeric polymermixed just prior to delivery through the inflation lumen 151. Thepolymer thus allows the balloon to conform to the outer stomach wall andsurrounding tissue to secure the anchor 340 to outer surface 100 a ofthe stomach wall. The balloon is preferably designed and the inflationmedium is selected to provide an inflated distal end that issufficiently firm to secure the anchor 340 in place while havingsufficient surface area and being malleable enough that the anchor issealed into place in a relatively atraumatic manner.

[0098] The anchor 340 further comprises ratchets 365 on the outercircumference of the elongate member 341 and a sealing bumper ring 366having an opening 367 forming an inner circumferential wall with ratchetteeth 368 for engaging the ratchets 365 on the elongate member 341. Thebumper ring 366 is moveable in a distal direction to sealingly securethe anchor 340 to the stomach wall and prevent distal movement of theanchor 340. The bumper ring 366 preferably has sufficient surface areaand is formed of an elastomer that spreads the load and minimizesfriction or other trauma to the stomach wall.

[0099] The anchor 340 further comprises electrode lumens 346, 347 havingopenings 346 a, 347 a in the elongate member 341. Conductor members 352,353 extend through the electrode lumens 346, 347, respectively, andinclude flexible conductors insulated along their length. The flexibleconductor members 352, 353 are preferably constructed of an elastic orsuperelastic alloy with an insulative coating. Electrically oppositeelectrodes 356, 357 are located on distal portions 360, 361 of moveableflexible conductor members 352, 353 respectively. Exposed electricalcontacts 354, 355 are located on the proximal portions of the conductormembers 352, 353. The electrical contacts 354, 355 are in electricalcontact with contacts 362, 363 respectively that are electricallycoupled to contacts in a main body of a stimulator unit in a mannersimilar to the sealing electrical connection of main body 20 and anchor123 described herein. The adjustable electrodes 356, 357 are containedwithin the electrode lumens 346, 347 when the anchor 340 is initiallyplaced as illustrated in FIG. 30A. The adjustable electrodes 356, 357are deployed within the stomach wall 100 by advancing the conductorsmembers 352, 353 distally through the electrode lumens 346, 347 wherethe openings 346 a, 347 a are configured to direct the electrodes 356,357 laterally from each other and within the stomach wall as illustratedin FIG. 30B. The electrodes 356, 357 are moved with respect to oneanother into a selectable optimal deployment position with an optimaldistance between the electrodes 356, 357.

[0100] An endoscopic instrument 370 is used to place the anchor 340,inflate the expandable member 348 and deploy the electrodes 356, 357.The instrument 370 is preferably used through the overtube 111, anopening 111 a or 111 b in the overtube 111 and/or through an instrumentchannel 114 in the endoscope 110 (while the procedure is visualizedthrough the endoscope 110.) The instrument 370 includes an inflationtube 373 removably attached to the inflation lumen 351 of the anchor340. The inflation tube 373 forms a continuous conduit with theinflation lumen 351 a conduit through which an inflation medium issupplied to inflate the expandable member 348. A push tube 371 comprisesa threaded end 371 a that engages the proximal end 342 a of the anchor340. The push tube 371 is used to advance the anchor 340 over the guidewire 334. An inner tube 372 includes prongs 374, 375 that engage theconductor members 352, 353 and are used to advance the electrodes 356,357 into the stomach wall by pushing the inner tube 372 while holdingthe anchor 340 in place with the push tube 371. The prongs 374, 375comprise electrically conductive wires that extend within the insulativematerial of the inner tube 372 to a stimulator/sensor circuit locatedexternally of the patient's body. The stimulator/sensor may be used todeliver test stimulation pulses to the stomach wall through theelectrodes 356, 357 or to measure the impedance of the stomach walltissue between the electrodes 356, 357. (e.g. to determine sufficientresponse to stimulation, sense electrical activity). The stimulationresponse may be determined by observing through the endoscope,contractions of the stomach wall, or by determining contractions usingone or more sensors, e.g. as described with respect to the variousembodiments herein.

[0101] After the anchor 340 is in place, an inflation medium is suppliedthrough the inflation tube 373 to inflate the expandable member 348adjacent the outside 100 a of the stomach wall. The inflation tube 373has a thin walled region at its distal end where it joins the inflationlumen 351. After the expandable member 348 is inflated, the inflationtube is removed by twisting or pulling the tube to break it away fromthe anchor 340. The push tube 374 serves to hold the anchor 340 intoplace in the stomach wall as the inflation tube 373 is disengaged. Thebumper ring 366 is then advanced distally to engage the inner wall ofthe stomach with ratchets 365 engaging ratchets 368 to prevent furtherdistal movement of the anchor through the stomach wall. After the anchor340 is in place, the push tube 371 may be removed by unthreading the end371 a on the push tube 371 from the threaded end 372 a of the anchor340. A stimulator unit such as the main body portion 20 described hereinis coupled to the anchor 340 in a manner similar to that describedherein with reference to anchor 123 with electrical contacts 354, 355coupled to the electronics unit within the stimulator through electricalcontacts362, 363. Electrical contacts 362, 363 are to be coupled to astimulator unit in as similar manner as are contacts 28, 28 a, or 28 bdescribed herein.

[0102] Alternatively the laterally extending conductive members 352, 353may be used to secure the anchor to the stomach wall without requiringan additional expandable distal portion.

[0103] Referring to FIGS. 31A and 31B an alternative stimulator 380 isillustrated comprising a main body portion 382 and an anchor 383. Theanchor 383 includes an expandable distal end 385 for securing the anchorto the stomach wall, seals 398 for sealing the anchor electricalcontacts 394, 395 and electrical contacts 396, 397 of the housing fromthe acidic environment of the stomach. A notch 384 in the anchor isarranged to engage a latch 399 in the main body 382 to couple the anchor383 and the main body 382 together so that contacts 396, 397 of thehousing 382 are in electrical contact with anchor contacts 394, 395,respectively. The anchor 383 further comprises insulated flexibleconductors 386, 387 extending from the anchor 383. The conductors 386,387 are coupled to electrode anchors 388, 389 that are constructed andattached to the stomach wall in a manner similar to the anchors 324, 325described herein with reference to FIGS. 28A and 28B.

[0104]FIG. 32 illustrates an alternative embodiment of an anchor deviceof the present invention. Anchor 410 comprises a screw connector 411located on the distal end 413 of the anchor 410. The screw 411 includeselectrode 416 coupled by way of a conductor extending through the anchor410 to electrical contact 418. The distal portion of the screw mayinclude a retaining element 419 to prevent dislodgement of the screwfrom the stomach wall. The anchor 410 includes a notch 414 for engaginga latch in a stimulator unit similar to the main body 20 describedherein, so that the electrical contact 418 is in electrical contact witha stimulator unit electrical contact similar to contact 28, 28 a, or 28b of a main body 20 described herein. An endoscopic instrument engagesthe proximal end 412 of the anchor 410 and rotates the anchor 410 sothat it is secured to a stomach wall.

[0105]FIGS. 33A and 33B illustrate an alternative embodiment of ananchor of the present invention. Anchor 420 comprises an elongate body421 having a proximal portion 422 and a distal portion 423. Anchor alsoincludes a notch 424 and electrical contact 428 located on the elongatebody 421. The notch 424 is arranged to couple the anchor to a stimulatorunit such as main body 20 described herein so that the electricalcontact 428 is in electrical communication with an electrical contact onthe housing such as contacts 28, 28 a, or 28 b, described herein. Anchor420 also comprises a clip 425 consisting of prongs 425 a and 425 b,preferably constructed of titanium with an insulative coating. Anexposed electrode area 426 is located on prong 425 a. The prong 425 a iscoupled by way of electrical conductor 429 to electrical contact. Theprongs 425 a, 425 b are coupled to lever arms 430 a, 430 b that rotateabout spring loaded hinge 432 so that the prongs 425 a, 425 b tendtowards a closed position as illustrated in FIG. 33B. Wires 431 a, 431 b(or strings) are attached to the lever arms 430 a, 430 b respectively.Wires 431 a , 431 b are also attached to an actuating wire 433 thatextends through the proximal portion 422 of the anchor 420 where it isattached to a handle 434. The handle 434 may be retracted in a proximaldirection to pull on the lever arms 430 a, 430 b to open the clip 425 asillustrated in FIG. 33A. When the handle 434 is released, the springload clip 425 tends to close as shown in FIG. 33B so that the prongs 425a, 425 b are secured within the stomach wall. As shown in FIG. 33A anendoscopic instrument 436 comprising a push tube 437 and a grasper 438is used to attach the clip 425 to the stomach wall. The push tube 437engages the proximal portion 422 of the anchor 420 to advance the anchorto a site for attaching the anchor to the stomach wall. A grasper 438extends through the push tube and includes a grasping end effector 439having grasping arms 439 a and 439 b that rotate about hinge 440 whichis coupled to an actuating device extending through the push tube 437out of the patient's mouth. The grasping arms are used to grasp thehandle 434 of the anchor and the grasper 438 is retracted from the pushtube 437 to pull the handle to open the clip, as illustrated in FIG.33A. The clip 425 is advanced to the site on the stomach wall forattachment. The handle 434 is then released so that the prongs 425 a and425 b engage the stomach wall with electrode 426 in electrical contactwith the wall. A stimulator unit may then be attached to the anchor in amanner similar to the attachment of anchor 123 and main body 20described herein.

[0106] Referring now to FIGS. 34A and 34B an alternative device isillustrated for attachment to the wall of the stomach or other organ.The device 450 comprises an electronics unit 455 located in a main bodyportion 451. The device further comprises an attachment device 454 forattaching the main body portion 451 to the inside 100 b of the stomachwall 100. The attachment device 454 comprises a clip 465 consisting ofprongs 465 a and 465 b. The prongs 465 a and 465 b include one or moresensors or therapeutic devices located thereon. Preferably, the sensoror therapeutic devices comprises electrodes 466 and 467 located onprongs 465 a, and 465 b respectively. The prongs 465 a and 465 b arepreferably constructed of titanium with an insulative coating. Theprongs 465 a 465 b are coupled by way of electrical conductors 469 a,469 b respectively to electronics unit 455. The prongs 465 a, 465 b arecoupled to lever arms 470 a, 470 b that rotate about spring loaded hinge472 so that the prongs 465 a, 465 b tend towards a closed positionillustrated in FIG. 34B. Wires 471 a, 471 b (or strings) are attached tothe lever arms 470 a, 470 b respectively. Wires 471 a and 471 b are alsoattached to an actuating wire 473 that extends through the proximalportion 462 of the device 450 where it is attached to a handle 474. Thehandle 474 may be retracted in a proximal direction to pull on the leverarms 470 a, 470 b to open the clip 465 as illustrated in FIG. 34A. Whenthe handle 474 is released, the spring load clip 465 tends to close asshown in FIG. 34B so that the prongs 465 a, 465 b are secured within thestomach wall. An endoscopic instrument may be used to place the device450 or to remove the device, by manipulating the handle 474.

[0107] The electronics unit 455 comprises an electromagnetic coil 456for inductively receiving power from an external source. Theelectromagnetic coil 456 is coupled to a voltage regulating circuit 457,which is coupled to electrodes 466, 467. The voltage regulating circuit457 operates to convert a high frequency AC signal to a regulatedvoltage signal that acts as a stimulation burst delivered to the stomachwall through electrodes 466, 467. Stimulation pulses in accordance witha stimulation program may be supplied to the electrodes 466, 467 whichmay act as electrically opposite bipolar electrodes. A plurality ofdevices 450 may be placed in various locations in the stomach wall.Preferably each device has electronics operating at a frequencydifferent from the other devices or operating at the same frequency butresponding to digital commands that are different for each device, sothat the stimulation program may selectively stimulate various locationsin the stomach. Additionally or alternatively, the devices 450 may actas sensors sensing electrical characteristics of the stomach wall. Also,other passive sensors may be located on the device. The sensors maysense a parameter of the stomach wall and transmit a representativesignal to an external device via the electromagnetic coil when promptedby an external power signal.

[0108] Referring to FIGS. 35A and 35B, an endoscopic instrument 480 isused to map electrical activity in the stomach wall and to identify andcharacterize the response of the stomach wall to various electricalstimulation parameters. The instrument 480 comprises an elongateflexible member 481 generally formed of a coil 482 with a lumen 483extending therethrough. An end effector 484 is located at the distal endof the instrument 480. The end effector 484 comprises electrode members486, 487 coupled together by a hinge 485. The electrode members 486, 487include electrodes 488, 489 located at the ends of the members 486, 487.The electrodes 488, 489 are coupled through conductors 490, 491extending through electrode members 486, 487 to wires 492, 493 whichextend through the lumen 483 in the instrument 480 to a proximallylocated handle 499. The wires 492, 493 are coupled to an externalstimulator/recorder unit 498, which supplies stimulation energy toelectrodes 488, 489 through wires 492, 493 and records electricalactivity sensed by the electrodes through the wires 492, 493. Amechanical wire 494 is coupled to a hinge actuating device 495 andextends through the lumen 483 to handle 499. The electrode members 486,487 are initially in a closed position. When the wire 494 is moveddistally using handle 499, the hinge actuating device 495 rotates theelectrode members 486, 487 about hinge 485 to spread the electrodemembers 486, 487 and electrodes 488, 489 apart from each other. In thisposition (FIG. 35B), the electrodes may be placed on the stomach wall ata desired site to measure and record electrical activity, electricalparameters, or to provide electrical stimulation pulses to the stomachwall. Upon providing stimulation pulses to the stomach wall, theresponse of the stomach (e.g., the presence, absence or degree ofcontraction) may be observed, either visually or through a sensor (notshown) located on the end effector 484 that senses muscle contractions,such as, for example, a strain gauge. The ideal location for attaching astimulation device may be determined by sensing electrical activity,electrical parameters or by observing a location where stimulationresults in a desired response. Also the ideal stimulation parameters orprogram may also be determined with the device by observing the responseof a site to various stimulation parameters delivered by the endeffector 484.

[0109] The materials of the attachment devices, stimulators and housingsof the present invention are preferably selected for long-term use inthe stomach, i.e., two or more years. Suitable materials include thematerials described herein, such as those described with respect to theconstruction of the main body 20.

[0110] The invention has been described with reference to preferredembodiments and in particular to a gastric stimulator, the presentinvention contemplates that the attachment devices may be used to attacha number of functional devices to the wall of the stomach for sensingparameters of the stomach or its environment, or for diagnosing orproviding treatment to the stomach. The attachment device mayincorporate such sensing, diagnostic or treatment devices within theattachment device. Such functional devices may also be separatelyattached to the stomach and/or to the attachment device or to anotherfunctional device. The attachment device or functional devices maycommunicate to an external recorder or controller by way of telemetry.They may be battery powered or powered by inductive coupling. Aplurality of functional devices may be attached to the stomach wall. Thefunctional devices may be programmed to respond to information orsignals delivered by other functional devices whether the signals aredelivered from one device to another through conductors or whether thesignals are delivered, e.g. through the stomach wall or medium withinthe stomach.

[0111] It is also contemplated that instruments described herein toattach or remove the attachment devices and stimulators may be used toattach and remove a variety of functional devices or to perform a numberof different endoscopic procedures. Alternative mechanisms for attachingthe various elements to the stomach wall are also contemplated,including for example staples, sutures and other means.

[0112] While the invention has been described with reference topreferred embodiment, it will be understood that variations andmodifications may be made within the scope of the following claims. Suchmodifications may include substituting elements or components whichperform substantially the same function in substantially the same way toachieve substantially the same result that the invention can bepracticed with modification within the scope of the following claims.

What is claimed is:
 1. A gastric stimulation device comprising: ahousing; electronic circuitry contained within the housing; at least onestimulating electrode coupled to the housing and electrically coupled tothe electronic circuitry; and an attachment device coupled to thehousing and operative to attach said housing within a stomach cavity toa stomach wall so that said at least one stimulating electrode is inelectrical contact with the stomach wall; wherein said electroniccircuitry is configured to deliver electrically stimulating signals tothe stomach through the at least one stimulating electrode.
 2. Thegastric stimulation device of claim 1, wherein said attachment devicecomprises an anchor having a first portion arranged to extend into thestomach wall when said anchor is attached to the stomach wall.
 3. Thegastric stimulation device of claim 2 wherein when said attachmentdevice is deployed, said first portion extends through said stomach wallin an orientation substantially perpendicular to said stomach wall. 4.The gastric stimulation device of claim 2 wherein said attachment devicefurther comprises at least one lateral extending member arranged to bedeployed to extend laterally of the attachment device within the stomachwall.
 5. The gastric stimulation device of claim 4 wherein said at leastone laterally extending member is configured to secure the attachmentdevice to the stomach wall.
 6. The gastric stimulation device of claim 4wherein said at least one laterally extending member comprises anelectrode located thereon.
 7. The gastric stimulation device of claim 4wherein said at least one laterally extending member comprises a straingauge located thereon.
 8. The gastric stimulation device of claim 6wherein said laterally extending member is adjustable.
 9. The gastricstimulation device of claim 4 wherein said at least one laterallyextending member comprises a plurality of laterally extending members.10. The gastric stimulation device of claim 9 wherein each of saidplurality of laterally extending members comprises an electrode thereon.11. The gastric stimulation device of claim 9 wherein said plurality oflaterally extending members are selectably adjustable with respect toone another to vary the distance between each of said electrodes. 12.The gastric stimulation device of claim 2 wherein said attachment devicefurther comprises a distal portion wherein when said attachment deviceis deployed, said distal portion extends through said stomach wall,adjacent an outer surface of the stomach wall.
 13. The gastricstimulation device of claim 2 wherein said at least one electrode islocated on said first portion of said anchor.
 14. The gastricstimulation device of claim 13 wherein said at least one electrode isarranged on said first portion so that said at least one electrode islocated within the stomach wall when said anchor is attached to thestomach wall.
 15. The gastric stimulation device of claim 2, whereinsaid anchor is permanently fixed to said housing.
 16. The gastricstimulation device of claim 2, wherein said anchor is removablyattachable to said housing.
 17. The gastric stimulation device of claim1, wherein said attachment device comprises a release mechanismoperative to release an attached stimulator.
 18. The gastric stimulationdevice of claim 1 wherein said stimulator comprises a release mechanismoperative to release the stimulator from the attachment device.
 19. Thegastric stimulation device of claim 1 wherein said attachment devicecomprises a release mechanism operative to release said attachmentdevice from engagement with the stomach wall.
 20. The gastricstimulation device of claim 2 wherein said anchor comprises: anexpandable distal portion adjacent to said first portion, saidexpandable distal portion arranged to secure the attachment device tothe stomach wall.
 21. The gastric stimulation device of claim 20 whereinsaid expandable distal portion comprises a spring mechanism biased in anexpanded position.
 22. The gastric stimulation device of claim 20wherein said expandable distal portion comprises an inflatable member.23. The gastric stimulation device of claim 22 further comprising aninflation medium for inflating said inflatable member
 24. The gastricstimulation device of claim 22 wherein said inflatable medium comprisesa curable polymer
 25. The gastric stimulation device of claim 22 whereinsaid inflatable member is inflatable to a predetermined pressure
 26. Thegastric stimulation device of claim 22 wherein said inflatable member ininflatable to a predetermined volume
 27. The gastric stimulation deviceof claim 20 wherein said at least one electrode is located on saidexpandable distal portion.
 28. The gastric stimulation device of claim20 wherein said expandable distal portion further comprises anantibiotic material coated on at least a portion of said expandabledistal portion.
 29. The gastric stimulation device of claim 2 whereinsaid first portion comprises a distal end having a sharp tip locatedthereon.
 30. The gastric stimulation device of claim 29 wherein said tipcomprises a bioabsorbable material.
 31. The gastric stimulation deviceof claim 1, wherein said at least one electrode is located on saidhousing.
 32. The gastric stimulation device of claim 1 wherein said atleast one electrode is coupled to said housing.
 33. The gastricstimulation device of claim 1, wherein said at least one electrode islocated on said attachment device.
 34. The gastric stimulation device ofclaim 1 wherein said at least one electrode is coupled to saidattachment device.
 35. The gastric stimulation device of claim 1,wherein said at least one electrode comprises a first and second bipolarelectrode, said first electrode being electrically opposite of saidsecond electrode.
 36. The gastric stimulation device of claim 35,wherein said first electrode is located on said attachment device andsaid second electrode is located on said housing.
 37. The gastricstimulation device of claim 35 wherein said first electrode is coupledto said attachment device and wherein said second electrode is coupledto said housing.
 38. The gastric stimulation device of claim 35, whereinsaid first and second electrodes are located on said housing.
 39. Thegastric stimulation device of claim 35, wherein each of said first andsecond electrode are coupled to said housing.
 40. The gastricstimulation device of claim 35, wherein said first and second electrodesare located on said attachment device
 41. The gastric stimulation deviceof claim 35, wherein said first and second electrodes are coupled tosaid attachment device.
 42. The stimulation device of claim 1 whereinsaid electronic circuitry comprises an electromagnetic coil arranged toreceive a telemetry signal from an external device.
 43. The stimulationdevice of claim 42 wherein said telemetry signal comprises arepresentative command signal for causing said device to provideelectrical stimulation to the stomach wall through said at least oneelectrode.
 44. The stimulation device of claim 42 further comprising auser operated external device comprising a second electromagnetic coil,said second electromagnetic coil arranged to emit said telemetry signal.45. The gastric stimulation device of claim 1 further comprising anexternal control unit, wherein said external unit is configured todeliver and said electronic circuitry is controlled to receive a controlsignal controlling the delivery of the electrically stimulating signals.46. The gastric stimulation device of claim 45 wherein said externalcontrol unit further comprises a patient actuatable control devicecoupled to said external control unit, wherein said patient actuablecontrol device is configured to instruct the external control unit totransmit said control signal upon patient actuation of the controldevice.
 47. A gastric stimulation device comprising: a housingconstructed of a first material resistant to corrosion when locatedwithin a stomach environment; said housing including an electroniccircuit within the housing and an electrical connector arranged toelectrically couple at least one stimulating electrode to saidelectronic circuit; and a sealing device operative to seal saidconnector from the stomach environment, wherein said sealing device isconstructed of a second material resistant to corrosion from the stomachenvironment.
 48. The gastric stimulation device of claim 47 wherein saiddevice further comprises at least one stimulating electrode coupled tothe housing and the electronic circuit through said connector.
 49. Thegastric stimulation device of claim 47 further comprising an attachmentdevice coupled to the housing and arranged to secure said housing to thestomach wall from within stomach cavity; wherein said electroniccircuitry is arranged to deliver electrically stimulating signals to thestomach through at least one stimulating electrode.
 50. The gastricstimulation device of claim 47 wherein said first and second materialare the same.
 51. The gastric stimulation device of claim 47 whereinsaid first corrosion resistant material is suitable for long-term usewithin a stomach.
 52. The gastric stimulation device of claim 47 whereinsaid second corrosion resistant material is suitable for long-term usewithin a stomach.
 53. A gastric stimulation device comprising: a housingconstructed of a material resistant to corrosion when located within astomach environment; said housing including an electronic circuit withinthe housing; and at least one stimulating electrode arranged so thatwhen deployed said at least one stimulating electrode is coupled to thehousing and is electrically coupled to the electronic circuit, whereinsaid electrode is formed of an electrically conductive materialresistant to corrosion when located within a stomach environment, andwherein said electronic circuitry is arranged to deliver electricallystimulating signals to the stomach wall through the at least oneelectrode.
 54. The gastric stimulation device of claim 53 wherein saidcorrosion resistant material is suitable for long-term use within astomach.
 55. The gastric stimulation device of claim 53 wherein saidelectrically conductive corrosion resistant material is suitable forlong-term use within a stomach.
 56. A gastric stimulation devicecomprising an anchor for attaching an electrode to a wall of a stomach,said anchor including: a first portion arranged to extend into thestomach wall, said first portion comprising a distal end having a sharptip located thereon and an expandable distal portion arranged to securethe anchor to the stomach wall.
 57. The gastric stimulation device ofclaim 56 wherein said tip comprises a bioabsorbable material.
 58. Agastric stimulation device comprising an anchor for attaching anelectrode to a wall of a stomach, said anchor including: a first portionarranged to extend into the stomach wall from within the stomach so thatsaid electrode is in electrical contact with the stomach wall.
 59. Thestimulation device of claim 58 wherein said first portion comprises adistal portion having an expandable portion arranged to expand to securethe anchor to the stomach wall.
 60. The stimulation device of claim 58wherein the at least one electrode is located on said first portion ofthe anchor.
 61. The stimulation device of claim 59 wherein saidexpandable portion is constructed to extend through the stomach wall andto expand adjacent on outer surface of the stomach wall.
 62. Thestimulation device of claim 58 wherein said expandable portion isconstructed to extend laterally into the stomach wall.
 63. Thestimulation device of claim 62 wherein said expandable portion comprisesat least one laterally advancing member.
 64. The stimulation device ofclaim 61 further comprising a bumper arranged to prevent furthermovement of the first portion through the stomach wall.
 65. A gastricstimulation device comprising: a housing; electronic circuitry containedwithin the housing; at least one stimulating electrode coupled to thehousing and electrically coupled to the electronic circuitry; anattachment device coupled to the housing and arranged to attach saidhousing within a stomach cavity to a stomach wall; and a sensor coupledto said stimulation device, said sensor operative to sense a parameterindicative of a condition the stomach, wherein said electronic circuitryis configured to deliver electrically stimulating signals to the stomachthrough the at least one stimulating electrode.
 66. The stimulationdevice of claim 65 wherein said sensor comprises a pH sensing device.67. The stimulation device of claim 65 wherein said sensor comprises astrain gauge.
 68. The stimulation device of claim 67 wherein said straingauge is located on said anchor.
 69. The stimulation device of claim 65wherein said sensor comprises a temperature sensing device.
 70. Thestimulation device of claim 65 wherein said sensor comprises said atleast one electrode and wherein said electronic circuitry comprises animpedance determining circuit coupled to said at least one electrode.71. The stimulation device of claim 65 wherein said sensor comprisessaid at least one electrode arranged to sense electrical activity of thestomach wall, and wherein said electronic circuitry further comprises acircuit for determining said condition of the stomach from theelectrical activity of the stomach wall sensed by said at least oneelectrode.
 72. The stimulation device of claim 71 wherein saidelectronic circuitry comprises a controller coupled to said circuit fordetermining said condition, and a memory device coupled to saidcontroller, said memory device including a stimulation program, whereinsaid controller is arranged to cause said at least one electrode todeliver a stimulation program responsive to said sensed electricalactivity.
 73. The stimulation device of claim 65 wherein said electroniccircuitry comprises: a controller coupled to said sensor, wherein saidsensor is arranged to provide an electrical signal representative ofsaid sensed information to said controller; and a memory device coupledto said controller, said memory device including a stimulation program,wherein said controller is arranged to cause said at least one electrodeto deliver the stimulation program responsive to said sensed condition.74. The stimulation device of claim 73 wherein said electronic circuitryfurther comprises a electromagnetic coil arranged to receive an externaltelemetry signal including the stimulation program from an externalprogrammer for storage in said memory device.
 75. The stimulation deviceof claim 65 wherein said electronic circuit comprises an electromagneticcoil arranged to send a telemetry signal to an external device, saidtelemetry signal including information representative of the sensedcondition, wherein said electromagnetic coil is further arranged toreceive a responsive telemetry signal from an external device, saidresponsive telemetry signal including instructions responsive to saidinformation representative of the sensed condition.
 76. A gastricstimulation device comprising: a housing; electronic circuitry containedwithin the housing; at least one stimulating electrode coupled to anelectrode anchoring device, said anchoring device arranged to attach theat least one electrode in electrical contact with a stomach wall,wherein said at least one electrode when deployed, is electricallycoupled to the electronic circuitry; and an attachment device coupled tothe housing and operative to attach said housing within the stomach tothe stomach wall; wherein said electronic circuitry is configured todeliver electrically stimulating signals to the stomach through the atleast one stimulating electrode.
 77. The gastric stimulation device ofclaim 76 wherein said at least one electrode is electrically coupled tothe electronic circuitry by a flexible lead.
 78. The gastric stimulationdevice of claim 77 wherein said at least one electrode is coupledthrough said attachment device to the electronic circuitry.
 79. Thegastric stimulation device of claim 76 wherein said at least oneelectrode is coupled through said housing to said electronic circuitry.80. The gastric stimulation device of claim 76 wherein said anchoringdevice comprises a first portion arranged when deployed to extend intothe stomach wall, said first portion comprises a distal end having asharp tip located thereon and an expandable distal portion arranged tosecure the anchoring device to the stomach wall.
 81. The gastricstimulation device of claim 80 wherein said tip comprises abioabsorbable material.
 82. An attachment device for attaching afunctional device to a stomach wall comprising: a securing deviceoperative to secure the attachment device to the stomach wall, saidsecuring device comprising a first portion at least a portion of whichis arranged to extend into the stomach wall when said attachment deviceis attached to the stomach wall; a coupling device arranged to receiveand couple the functional device to the attachment device.
 83. Theattachment device of claim 82, wherein said attachment device isremovably attachable to the functional device.
 84. The attachment deviceof claim 82 wherein said attachment device further comprises areleasable latching mechanism.
 85. The attachment device of claim 82wherein said coupling device includes a quick release mechanism.
 86. Theattachment device of claim 82 wherein said first portion is configuredto extend through said stomach wall in an orientation substantiallyperpendicular to said stomach wall.
 87. The attachment device of claim82 wherein said first portion comprises a strain gauge located thereon.88. The attachment device of claim 82 further comprising at least onelateral extending member arranged to be deployed to extend laterally ofthe first portion within the stomach wall.
 89. The attachment device ofclaim 88 wherein said at least one laterally extending member isconfigured to secure the attachment device to the stomach wall.
 90. Theattachment device of claim 88 wherein said at least one laterallyextending member comprises an electrode located thereon.
 91. Theattachment device of claim 82 wherein said attachment device isremovably attachable to said stomach wall.
 92. The attachment device ofclaim 82 further comprising: an expandable distal portion coupled tosaid first portion, said expandable distal portion arranged to securethe attachment device to the stomach wall.
 93. The attachment device ofclaim 92 wherein said further comprising a bumper arranged to engagesaid attachment device so that said bumper abuts the inner surface ofthe stomach wall.
 94. The attachment device of claim 92 wherein saidexpandable distal portion further comprises an antibiotic materialcoated on at least a portion of said expandable distal portion.
 95. Theattachment device of claim 92 wherein said expandable distal portioncomprises a spring mechanism biased in an expanded position.
 96. Theattachment device of claim 92 wherein said expandable distal portioncomprises an inflatable member.
 97. The attachment device of claim 96further comprising: an inflation lumen in fluid communication with saidinflatable member and an inflation medium for inflating said inflatablemember.
 98. The attachment device of claim 96 wherein said inflationmedium comprises a curable polymer.
 99. The attachment device of claim96 wherein said inflatable member is inflatable to a predeterminedpressure
 100. The attachment device of claim 96 wherein said inflatablemember is inflatable to a predetermined volume.
 101. The attachmentdevice of claim 88 further comprising a distal portion wherein when saidattachment device is deployed, said distal portion extends through saidstomach wall, adjacent an outer surface of the stomach wall.
 102. Theattachment device of claim 101 wherein said distal portion comprises anexpandable member.
 103. The attachment device of claim 101 wherein saiddistal portion further comprises an antibiotic material coated on atleast a portion of said distal portion.
 104. The attachment device ofclaim 82 wherein said first portion comprises a distal end having asharp tip located thereon.
 105. The attachment device of claim 104wherein said tip comprises a bioabsorbable material.
 106. The attachmentdevice of claim 82 wherein said securing device comprises a clip. 107.The attachment device of claim 106 wherein said clip is spring loaded.108. The attachment device of claim 82 wherein said securing devicecomprises a screw.
 109. An anchor for attaching to a stomach wallcomprising: a functional portion; and a securing portion operative toextend into the stomach wall in a direction substantially perpendicularto a plane of smooth stomach muscle contractions and thereby secure theattachment device to the stomach wall.
 110. The anchor of claim 109wherein said functional portion comprises a sensor.
 111. The anchor ofclaim 110 wherein said sensor comprises an electrode
 112. The anchor ofclaim 110 wherein sensor comprises a pH sensor.
 113. The anchor of claim110 wherein said sensor comprises a temperature sensor.
 114. The anchorof claim 110 wherein said sensor comprises a pressure sensor.
 115. Theanchor of claim 110 wherein said sensor comprises a strain gauge. 116.The anchor of claim 110 wherein said anchor further comprises anelectronic circuit including a telemetry circuit configured tocommunicate information sensed by said sensor to an external receiver.117. The anchor of claim 116 wherein said electronic circuit comprises abattery, said battery being operative to power said circuit.
 118. Theanchor of claim 117 wherein said electronic circuit is configured toreceive an inductively coupled power signal from an external source.119. The anchor of claim 109 wherein said functional portion comprises atherapeutic device.
 120. The anchor of claim 109 wherein said functionalportion comprises a therapeutic agent delivery device.
 121. The anchorof claim 109, wherein said securing portion includes an electrodelocated thereon.
 122. The anchor of claim 121 further comprisingelectronic circuit configured to provide electrically stimulating pulsesto a stomach wall through said electrode.
 123. The anchor of claim 109wherein said securing portion comprises a spring load clip.
 124. Theanchor of claim 109 wherein said securing portion comprises a screw.125. The anchor of claim 109 wherein said securing portion comprises anexpandable distal portion.
 126. The anchor of claim 125 wherein saidexpandable distal portion comprises at least one laterally extendingmember.
 127. The anchor of claim 126 wherein said at least one laterallyextending member is configured to secure the anchor to the stomach wall.128. The anchor of claim 126 wherein said at least one laterallyextending member comprises an electrode located thereon.
 129. The anchorof claim 125 wherein said expandable distal portion comprises aninflatable member.
 130. The attachment device of claim 125 wherein saidexpandable distal portion comprises a spring mechanism biased in anexpanded position.
 131. The anchor of claim 129 further comprising: aninflation lumen in fluid communication with said inflatable member andan inflation medium for inflating said inflatable member.
 132. Theanchor of claim 131 wherein said inflation medium comprises a curablepolymer.
 133. The anchor of claim 125 wherein said expandable member isarranged to expand adjacent an outer surface of the stomach wall. 134.The anchor of claim 125 wherein said securing portion further comprisesa bumper arranged to engage said attachment device so that said bumperabuts the inner surface of the stomach wall.
 135. The anchor of claim109 wherein said securing portion comprises a distal end having a sharptip located thereon.
 136. The anchor of claim 135 wherein said tipcomprises a bioabsorbable material.
 137. The anchor of claim 109 whereinsaid attachment device is removably attachable to said stomach wall.138. The anchor of claim 109 wherein said securing portion comprises aretaining portion arranged to prevent dislodgement of the anchor fromthe stomach wall.
 139. The anchor of claim 138 wherein said retainingportion comprises an expandable distal end.
 140. The anchor of claim 138wherein said retaining portion comprises a bumper.
 141. An anchor forattaching to a stomach wall comprising: a functional portion; a securingportion operative to extend into the stomach wall and thereby secure theattachment device to the stomach wall; and a retaining portion arrangedto prevent dislodgement of the anchor from the stomach wall.
 142. Theanchor of claim 141 wherein said retaining portion comprises a springportion arranged to bias said securing portion in a stomach engagingposition.
 143. The anchor of claim 141 wherein said securing portioncomprises a clip.
 144. The anchor of claim 141 wherein said securingportion comprises a staple.
 145. The anchor of claim 141 wherein saidsecuring portion comprises a suture.
 146. An endoscopic instrumentcomprising: an elongate tube comprising a proximal portion, a distalportion and a circumferential wall forming a first lumen sized toreceive an endoscope therethrough; and at least one instrument channelextending within the circumferential wall from the proximal portion tothe distal portion and configured to receive an instrument therethrough.147. An endoscopic instrument system for piercing a stomach wallcomprising: a piercing needle; and an elongate member comprising adistal portion having a first axis; a lumen extending along a secondaxis parallel to said first axis; and a wall engaging portion located onsaid distal portion, wherein said piercing needle is arranged to extendthrough said lumen so that at said distal portion it is substantiallyparallel to said second axis so as to pierce the stomach wall in anorientation substantially perpendicular to said stomach wall.
 148. Theendoscopic instrument system of claim 147wherein said wall engagingmember is arranged to engage and hold tissue of a stomach wall.
 149. Theendoscopic instrument system of claim 148 wherein said wall engagingportion comprises a suction cup and a vacuum source operative to supplya vacuum pressure to said suction cup.
 150. The endoscopic instrumentsystem of claim 147 further comprising an anchor engaging instrumentcomprising an elongate member having a distal portion and an anchorengaging portion.
 151. The endoscopic instrument system of claim 147wherein said piercing needle comprises a hollow needle with a guide wirelumen extending therethrough said guide wire lumen for removablyreceiving a guide wire.
 152. The endoscopic instrument system of claim151 further comprising a guide wire and an anchor having a guide wirelumen extending therethrough, wherein when said hollow needle is removedfrom said guide wire, said anchor is arranged to advance over said guidewire.
 153. The endoscopic instrument system of claim 151 furthercomprising a sheath having a lumen extending therethrough, said lumenhaving an inner diameter configured to removably receive said piercingneedle.
 154. The endoscopic instrument of claim 153 further comprisingan anchor having an outer diameter smaller than said inner diameter ofsaid lumen so that said anchor may be advanced through said lumen. 155.The endoscopic instrument system of claim 154 further comprising ananchor engaging instrument comprising an elongate member sized to fitwithin the lumen and including an anchor engaging portion.
 156. Theendoscopic instrument system of claim 147 further comprising a sheathhaving a lumen extending therethrough, said lumen having an innerdiameter configured to removably receive said piercing needle whereinsaid sheath comprises a dilator arranged to dilate an opening in thestomach wall.
 157. An endoscopic instrument comprising: an elongatemember having a proximal portion and a distal portion; at least oneelectrode located on said distal portion coupled to a conductorextending from said distal portion to said proximal portion; anelectronic circuit comprising an input and an output, said input coupledto said conductor at said proximal portion, said electronic circuitconfigured to receive sensed electrical signals at said electrode and tooutput a signal representative of said sensed signal on said output.158. An endoscopic system comprising: an elongate stimulation memberhaving a proximal portion and a distal portion; at least one electrodelocated on said distal portion coupled to a conductor extending fromsaid distal portion to said proximal portion; and an electronic circuitcomprising an output, said output coupled to said conductor at saidproximal portion, said electronic circuit configured to deliver astimulation signal to said electrode; and a sensing member having asensor operative to sense a response of a stomach wall to thestimulation signal.
 159. The endoscopic system of claim 158 wherein saidsensing member is located on said elongate stimulation member
 160. Theendoscopic system of claim 158 wherein said sensing member is located onan elongate sensing instrument.
 161. The endoscopic system of claim 158wherein said sensing member comprises an endoscopic visualizationportion.
 162. The endoscopic system of claim 158 wherein said sensingmember comprises a strain gauge.
 163. The endoscopic system of claim 158wherein said sensing member comprises a pressure sensor.
 164. A systemfor providing electrically stimulating signals to a stomach wallcomprising: a) a gastric stimulator including: a housing havingelectronic circuitry contained therein and including an electricalconductor arranged to electrically couple at least one electrode to theelectronic circuitry, wherein the electronic circuitry is configured todeliver electrically stimulating signals to the stomach wall through atleast one stimulating electrode; and b) an attachment device operativeto attach the housing to the inside of stomach wall; c) an endoscopicdelivery device comprising: an elongate member having a proximal portionand a distal portion; a stimulator engaging portion located at saiddistal portion of the elongate member, said stimulator engaging portionarranged to advance the gastric stimulator through an esophagus andtowards an attachment site within the stomach.
 165. The system of claim164 further comprising at least one stimulating electrode located on thehousing.
 166. The system of claim 164 further comprising at least onestimulating electrode and an electrode attachment device arranged toattach the at least one electrode to the stomach wall; and an endoscopicattachment instrument arranged to place the at least one electrode in anattached position on the stomach wall.
 167. The system of claim 166wherein the electrode attachment device comprises a first portionarranged to extend into the stomach wall.
 168. The system of claim 167wherein said first portion comprises an expandable distal portionarranged to secure the attachment device to the stomach wall.
 169. Thesystem of claim 167 wherein the at least one electrode is located onsaid first portion of the attachment device.
 170. The system of claim164 wherein said stimulator engaging portion comprises a releasableconnector and wherein said stimulator further comprises a toolconnector, said releasable connector arranged to releasably engage thetool connector for stimulator deployment.
 171. The system of claim 164wherein said attachment device is releasably attachable to the housing.172. The system of claim 164 wherein the attachment instrument includesa guide coupled to the attachment device and wherein said housingincludes a guide opening for receiving the guide.
 173. The system ofclaim 172 wherein said guide comprises a tether.
 174. The system ofclaim 172 wherein said tether is flexible.
 175. The system of claim 172wherein said guide comprises a guide wire.
 176. A system for providingelectrically stimulating signals to a stomach wall comprising: a) agastric stimulator including: a housing having electronic circuitrycontained therein and including an electrical conductor arranged toelectrically couple at least one electrode to the electronic circuitry,wherein the electronic circuitry is configured to deliver electricallystimulating signals to the stomach wall through at least one stimulatingelectrode; and b) an attachment device operative to attach the housingto the inside of stomach wall; and c) an endoscope comprising: anelongate member having a proximal end and a distal end; a stimulatorengaging portion located at said distal end of the elongate member, saidstimulator engaging portion arranged to advance the gastric stimulatorthrough an esophagus and towards an attachment site within the stomach.177. The system of claim 176 wherein said endoscope comprisesvisualization portion arranged to visualize a site on the inside of astomach wall for attaching a stimulating device.
 178. The system ofclaim 176 wherein said attachment device comprises an anchor, andwherein the endoscope further comprises an instrument channel extendingfrom the proximal portion to the distal end of the elongate member; andwherein the anchor is sized to extend through the instrument channel inthe endoscope for delivery to an attachment site on the inside of astomach wall.
 179. A system for attaching a functional device to astomach wall comprising: an attachment device having a first portionarranged to extend into the stomach wall when said attachment device isattached to the stomach wall; and an endoscopic delivery devicecomprising: an elongate member having a proximal end and a distal end;an attachment device engaging portion extendable through a lumenextending through said elongate member, said attachment engaging portionarranged to advance the attachment device through an esophagus andtowards an attachment site within the stomach.
 180. The system of claim179 further comprising a functional device.
 181. The system of claim180, wherein said attachment device is releasably attachable to thefunctional device.
 182. The system of claim 179 further comprising afunctional device engaging tool wherein said functional device engagingtool comprises a releasable connector and wherein said functional devicefurther comprises a tool connector, said releasable connector arrangedto releasably engage the tool connector for functional device deployment183. The system of claim 179 wherein said attachment device comprises:an expandable distal portion coupled to said first portion, saidexpandable distal portion arranged to secure the attachment device tothe stomach wall.
 184. The system of claim 180 further comprising aguide coupled to the attachment device and wherein said functionaldevice includes a guide opening for receiving the guide.
 185. The systemof claim 184 wherein said guide comprises a tether.
 186. The system ofclaim 184 wherein said guide comprises a guide wire.
 187. A gastricstimulation device comprising: housing means for containing electroniccircuit means; electrode means coupled to the housing means andelectrically coupled to the electronic circuit means; electronic circuitmeans for delivering electrically stimulating signals to the stomachthrough said electrode means; and an attachment means for attaching saidhousing means within a stomach cavity to a stomach wall so that saidelectrode means is in electrical contact with the stomach wall.
 188. Thegastric stimulation device of claim 187 wherein said electrode meanscomprises at least one pair of bipolar electrodes, said stimulationdevice further comprising adjustable means for adjusting a distancebetween said bipolar electrodes.
 189. The gastric stimulation device ofclaim 187 further comprising a release means for latching and unlatchingsaid housing means with said attachment means.
 190. The gastricstimulation device of claim 187 further comprising a disengaging meansfor disengaging said attachment means from the stomach wall.
 191. Thegastric stimulation device of claim 187 further comprising expandablemeans for securing said attachment means to the stomach wall.
 192. Thegastric stimulation device of claim 187 wherein said electronic circuitmeans comprises telemetry means for sending or receiving a telemetrysignal.
 193. The gastric stimulation device of claim 187 furthercomprising a patient control means for controlling the electroniccircuit means through said telemetry means.
 194. The gastric stimulationdevice of claim 182 further comprising a control means for transmittinga telemetry signal to said telemetry means.
 195. The gastric stimulationdevice of claim 187 further comprising an electrode anchor means foranchoring said electrode means to a stomach wall so that said electrodemeans is in electrical contact with said stomach wall.
 196. The gastricstimulation device of claim 187 further comprising an electricallycoupling means for electrically coupling said electrode means to saidhousing means.
 197. A gastric stimulation device comprising: a corrosionresistant housing means for containing electronic circuit means;electronic circuit means for delivering electrically stimulating signalsto the stomach through an electrode means, said electronic circuit meanscomprising a connector means for electrically coupling the circuit meansto an electrode means; and a corrosion resistant sealing means forsealing said connector means from the stomach environment.
 198. Thegastric stimulation device of claim 197 further comprising an attachmentmeans for securing said housing to the stomach wall from within stomachcavity.
 199. A gastric stimulation device comprising: an anchor meansfor attaching an electrode to a wall of a stomach from within a stomachcavity.
 200. The gastric stimulation device of claim 199 wherein saidanchor means comprises an expandable means for securing the anchor to astomach wall.
 201. The stimulation device of claim 200 wherein saidanchor means comprises and electrode means located thereon.
 202. Agastric stimulation device comprising: housing means for containingelectronic circuit means; electrode means coupled to the housing meansand electrically coupled to the electronic circuit means; electroniccircuit means for delivering electrically stimulating signals to thestomach through said electrode means; and an attachment means forattaching said housing means within a stomach cavity to a stomach wallso that said electrode means is in electrical contact with the stomachwall; and a sensing means for sensing a parameter indicative of acondition of the stomach.
 203. The gastric stimulation device of claim202 further comprising a control means for controlling the stimulationsignals based on a parameter sensed by said sensing means.
 204. Anattachment means for attaching a functional device means to a stomachwall comprising: a securing means for securing the attachment means to astomach wall; and a coupling means for receiving and coupling saidfunctional device means to said attachment device means.
 205. Theattachment means of claim 204 further comprising a releasable latchmeans for latching and unlatching said coupling means from a coupledengagement with a device attached to said attachment means.
 206. Theattachment means of claim 204 further comprising a release means forreleasing said attachment means from engagement with a stomach wall.207. The attachment means of claim 204 wherein said securing means isarranged to secure said attachment means in a substantiallyperpendicular orientation with respect to the natural orientation of thestomach wall.
 208. The attachment means of claim 204 further comprisingan expandable means for securing sand attachment means to a stomachwall.
 209. The attachment means of claim 208 wherein said expandablemeans comprises an inflatable means for sealingly securing saidexpandable means adjacent an outer surface of a stomach wall.
 210. Theattachment means of claim 204 further comprising a bumper means forengaging the attachment device so that said bumper means abuts an innersurface of a stomach wall.
 211. An anchor means for anchoring afunctional means to a stomach wall comprising: a securing means forextending into a stomach wall to secure said anchor means to; and afunctional means for treating or sensing a condition of a stomach. 212.The anchor means of claim 211 wherein said functional means comprises asensing means for sensing a parameter indicative of a condition of astomach.
 213. The anchor means of claim 211 wherein said functionalmeans comprises a therapeutic means for treating said stomach.
 214. Theanchor means of claim 211 further comprising a release means forreleasing said attachment means from engagement with a stomach wall.215. The anchor means of claim 211 wherein said securing means isarranged to secure said anchor means in a substantially perpendicularorientation with respect to the natural orientation of the stomach wall.216. The anchor means of claim 211 further comprising an expandablemeans for securing said attachment means to a stomach wall.
 217. Theanchor means of claim 216 wherein said expandable means comprises aninflatable means for sealingly securing said expandable means adjacentan outer surface of a stomach wall.
 218. The attachment means of claim211 further comprising a bumper means for engaging the anchor device sothat said bumper means abuts an inner surface of a stomach wall.
 219. Anendoscopic instrument system for piercing a stomach wall comprising: apiercing means for piercing the stomach wall in an orientationsubstantially perpendicular to said stomach wall; and a lumen meansreceiving said piercing means said lumen means having an axissubstantially parallel to said piercing means for receiving saidpiercing means therethrough, and having a wall engaging means forengaging and holding a portion of a stomach wall to be pierced by saidpiercing means.
 220. The endoscopic instrument system of claim 219wherein said wall engaging means comprises a vacuum means for applying avacuum to a region of the stomach wall to be pierced.
 221. Theendoscopic instrument of claim 219 wherein said piercing means comprisesmeans for advancing over a guide wire, said instrument furthercomprising a guide wire means for removably receiving said piercingmeans and for removably receiving an anchor means for anchoring in astomach wall.
 222. The endoscopic instrument of claim 219 wherein saidinstrument further comprises a sheath means for removably receiving saidpiercing means, said sheath means for receiving an anchor means foranchoring in a stomach wall.
 223. An endoscopic instrument systemcomprising: an elongate instrument means for accessing the inside of astomach wall through an esophagus, said elongate instrument means havinga distal portion; and an electrical signal sensing means for sensingelectrical activity of a stomach wall, said electrical signal sensingmeans located on said distal portion of said elongate instrument means.224. An endoscopic instrument system comprising: an elongate instrumentmeans for accessing the inside of a stomach wall through an esophagussaid elongate instrument means having a distal portion; an electricalstimulating means for electrically stimulating a stomach wall, saidstimulating means located on said distal portion of said elongateinstrument means; and a sensing means for sensing response of thestomach wall to electrical stimulation.
 225. The endoscopic instrumentsystem of claim 224 further comprising an adjusting means responsive tosaid sensing means, for adjusting parameter of stimulation applied tosaid stomach in response to a sensed response of the stomach wall to theelectrical stimulation.
 226. A method of stimulating a stomach wallcomprising the steps of: providing a gastric stimulator including ahousing containing electronic circuitry therein, wherein said electroniccircuitry is arranged to deliver electrically stimulating signals to thestomach wall through at least one stimulating electrode; providing anattachment device for attaching the stimulator to the stomach wall;providing at least one stimulating electrode; advancing the gastricstimulator through the esophagus of a patient and towards an attachmentsite within the patient's stomach; attaching the stimulator device tothe attachment site with the attachment device; and placing said atleast one stimulating electrode in electrical contact with the stomachwall, whereby the at least one stimulating electrode is coupled to theelectronic circuitry.
 227. The method of stimulating a stomach wall ofclaim 226 further comprising the steps of: providing an endoscopeincluding a device for identifying a site for attaching the stimulatorto the stomach wall; and identifying the attachment site with theendoscope before attaching the stimulator device to the attachment sitewith the attachment device.
 228. The method of stimulating a stomachwall of claim 226 further comprising the steps of: providing astimulator engaging device; and advancing the gastric stimulator throughthe esophagus and towards an attachment site within the stomach with thestimulator engaging device.
 228. A method of attaching a functionaldevice to a stomach wall comprising the steps of: providing a functionaldevice; providing an attachment device for attaching the functionaldevice to the stomach wall; advancing the attachment device through apatient's esophagus and towards an attachment site within the stomach;attaching the attachment device to the attachment site; advancing thefunctional device to the attachment device; and coupling the functionaldevice to the attachment device.
 229. The method of claim 228 furthercomprising the steps of: providing the functional device with anactuating circuit configured to actuate the functional device; andactuating the functional device by way of a control signal from saidactuating circuit to provide a functional response by the functionaldevice.
 230. The method of claim 229 further comprising the steps of:providing a telemetry circuit coupled to the actuating circuit; anddelivering a telemetry signal to the telemetry circuit to causegeneration of the control signal.
 231. A method of attaching afunctional device to a stomach wall comprising the steps of: providingan anchor including a functional portion and a securing portion;advancing the anchor through the esophagus and towards an attachmentsite within the stomach; and attaching the anchor to the attachment siteso that the securing portion does not substantially constrain thestomach in the plane of smooth muscle contractions.
 232. The method ofattaching a functional device to a stomach wall of claim 231 wherein thestep of attaching the anchor to the attachment site comprises attachingthe securing portion substantially perpendicular to the plane of thestomach wall.
 233. The method of attaching a functional device to thestomach wall of claim 231 further comprising the step of providing theanchor with an expandable distal end; wherein the step of attaching theanchor to the attachment site further comprises piercing the stomachwall and expanding the expandable distal end to secure the anchor to thestomach wall.
 234. A method of attaching a stimulating electrode to astomach wall comprising the steps of: providing an anchor including asecuring portion; advancing the anchor through a patient's esophagus andtowards an attachment site within the stomach; attaching the anchor tothe attachment site; providing an electrically stimulating electrode;advancing the electrically stimulating electrode through the esophagusand towards the anchor within the stomach; coupling the electricallystimulating electrode to the anchor so that the electrode is inelectrical contact with the stomach wall.
 235. A method of attaching astimulating electrode to a stomach wall comprising the steps of:providing an anchor including a securing portion and an electricallystimulating electrode advancing the anchor through the esophagus andtowards an attachment site within the stomach; and attaching the anchorto the attachment site so that the electrode is in electrical contactwith the stomach wall.
 236. A method of attaching a stimulatingelectrode to a stomach wall comprising the steps of: providing an anchorincluding a securing portion; advancing the anchor through the esophagusand towards an attachment site within the stomach; and attaching theanchor to the attachment site; providing an electrically stimulatingelectrode; advancing the electrically stimulating electrode through theesophagus and towards a stimulating site within the stomach; attachingthe electrically stimulating electrode to the stimulating site so thatthe electrode is in electrical contact with the stomach wall.